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1.
Cell ; 186(10): 2062-2077.e17, 2023 05 11.
Article in English | MEDLINE | ID: mdl-37075755

ABSTRACT

Entry of enveloped viruses into cells is mediated by viral fusogenic proteins that drive membrane rearrangements needed for fusion between viral and target membranes. Skeletal muscle development also requires membrane fusion events between progenitor cells to form multinucleated myofibers. Myomaker and Myomerger are muscle-specific cell fusogens but do not structurally or functionally resemble classical viral fusogens. We asked whether the muscle fusogens could functionally substitute for viral fusogens, despite their structural distinctiveness, and fuse viruses to cells. We report that engineering of Myomaker and Myomerger on the membrane of enveloped viruses leads to specific transduction of skeletal muscle. We also demonstrate that locally and systemically injected virions pseudotyped with the muscle fusogens can deliver µDystrophin to skeletal muscle of a mouse model of Duchenne muscular dystrophy and alleviate pathology. Through harnessing the intrinsic properties of myogenic membranes, we establish a platform for delivery of therapeutic material to skeletal muscle.


Subject(s)
Bioengineering , Lentivirus , Membrane Proteins , Muscle, Skeletal , Muscular Dystrophy, Duchenne , Animals , Mice , Cell Fusion , Membrane Fusion , Membrane Proteins/genetics , Membrane Proteins/metabolism , Muscle Development , Muscle, Skeletal/metabolism , Muscle, Skeletal/virology , Bioengineering/methods , Muscular Dystrophy, Duchenne/therapy , Disease Models, Animal , Viral Tropism , Lentivirus/genetics
3.
N Engl J Med ; 391(5): 393-407, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38828933

ABSTRACT

BACKGROUND: Belantamab mafodotin had single-agent activity in patients with relapsed or refractory multiple myeloma, a finding that supports further evaluation of the agent in combination with standard-care therapies. METHODS: In this phase 3, open-label, randomized trial, we evaluated belantamab mafodotin, bortezomib, and dexamethasone (BVd), as compared with daratumumab, bortezomib, and dexamethasone (DVd), in patients who had progression of multiple myeloma after at least one line of therapy. The primary end point was progression-free survival. Key secondary end points were overall survival, response duration, and minimal residual disease (MRD)-negative status. RESULTS: In total, 494 patients were randomly assigned to receive BVd (243 patients) or DVd (251 patients). At a median follow-up of 28.2 months (range, 0.1 to 40.0), median progression-free survival was 36.6 months (95% confidence interval [CI], 28.4 to not reached) in the BVd group and 13.4 months (95% CI, 11.1 to 17.5) in the DVd group (hazard ratio for disease progression or death, 0.41; 95% CI, 0.31 to 0.53; P<0.001). Overall survival at 18 months was 84% in the BVd group and 73% in the DVd group. An analysis of the restricted mean response duration favored BVd over DVd (P<0.001). A complete response or better plus MRD-negative status occurred in 25% of the patients in the BVd group and 10% of those in the DVd group. Grade 3 or higher adverse events occurred in 95% of the patients in the BVd group and 78% of those in the DVd group. Ocular events were more common in the BVd group than in the DVd group (79% vs. 29%); such events were managed with dose modifications, and events of worsening visual acuity mostly resolved. CONCLUSIONS: As compared with DVd therapy, BVd therapy conferred a significant benefit with respect to progression-free survival among patients who had relapsed or refractory multiple myeloma after at least one line of therapy. Most patients had grade 3 or higher adverse events. (Funded by GSK; DREAMM-7 ClinicalTrials.gov number, NCT04246047; EudraCT number, 2018-003993-29.).


Subject(s)
Antineoplastic Combined Chemotherapy Protocols , Bortezomib , Dexamethasone , Multiple Myeloma , Progression-Free Survival , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal/adverse effects , Antibodies, Monoclonal, Humanized/administration & dosage , Antibodies, Monoclonal, Humanized/adverse effects , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Bortezomib/administration & dosage , Bortezomib/adverse effects , Dexamethasone/administration & dosage , Dexamethasone/adverse effects , Kaplan-Meier Estimate , Multiple Myeloma/drug therapy , Multiple Myeloma/mortality , Neoplasm, Residual , Disease Progression
4.
J Am Soc Nephrol ; 2024 Oct 14.
Article in English | MEDLINE | ID: mdl-39401086

ABSTRACT

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) is caused by mutations in the PKD1 and PKD2 genes, and often progresses to kidney failure. ADPKD progression is not uniform among patients, suggesting that factors secondary to the PKD1/2 gene mutation could regulate the rate of disease progression. Here we tested the effect of circadian clock disruption on ADPKD progression. Circadian rhythms are regulated by cell-autonomous circadian clocks composed of clock proteins. BMAL1 is a core constituent of the circadian clock. METHODS: To disrupt the circadian clock, we deleted Bmal1 gene in the renal collecting ducts of the Pkd1RC/RC (RC/RC) mouse model of ADPKD (RC/RC;Bmal1f/f;Pkhd1cre, called DKO mice), and in Pkd1 knockout mouse inner medullary collecting duct cells (Pkd1Bmal1KO mIMCD3 cells). Only male mice were used. RESULTS: Human nephrectomy ADPKD kidneys showed altered clock gene expression when compared to normal control human kidneys. When compared to RC/RC kidneys, DKO kidneys showed significantly altered clock gene expression, increased cyst growth, cell proliferation, apoptosis and fibrosis. DKO kidneys also showed increased lipogenesis and cholesterol synthesis-related gene expression, and increased tissue triglyceride levels compared to RC/RC kidneys. Similarly, in vitro, Pkd1Bmal1KO cells showed altered clock genes, increased lipogenesis and cholesterol synthesis-related genes, and reduced fatty-acid oxidation-related gene expression compared to Pkd1KO cells. The Pkd1Bmal1KO cells showed increased cell proliferation compared to Pkd1KO cells, which was rescued by pharmacological inhibition of lipogenesis. CONCLUSIONS: Renal collecting duct specific Bmal1 gene deletion disrupted the circadian clock and triggered accelerated ADPKD progression by altering lipid metabolism-related gene expression.

5.
J Mol Cell Cardiol ; 195: 68-72, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39053573

ABSTRACT

Heart Failure with preserved ejection fraction (HFpEF) has a high rate of sudden cardiac death (SCD) and empirical treatment is ineffective. We developed a novel preclinical model of metabolic HFpEF that presents with stress-induced ventricular tachycardia (VT). Mechanistically, we discovered arrhythmogenic changes in intracellular Ca2+ handling distinct from the changes pathognomonic for heart failure with reduced ejection fraction. We further show that dantrolene, a stabilizer of the ryanodine receptor Ca2+ channel, attenuates HFpEF-associated arrhythmogenic Ca2+ handling in vitro and suppresses stress-induced VT in vivo. We propose ryanodine receptor stabilization as a mechanistic approach to mitigation of malignant VT in metabolic HFpEF.


Subject(s)
Arrhythmias, Cardiac , Calcium , Dantrolene , Disease Models, Animal , Heart Failure , Ryanodine Receptor Calcium Release Channel , Ryanodine Receptor Calcium Release Channel/metabolism , Animals , Calcium/metabolism , Heart Failure/metabolism , Heart Failure/drug therapy , Heart Failure/physiopathology , Arrhythmias, Cardiac/metabolism , Arrhythmias, Cardiac/drug therapy , Dantrolene/pharmacology , Stroke Volume/drug effects , Myocytes, Cardiac/metabolism , Myocytes, Cardiac/drug effects , Humans , Tachycardia, Ventricular/metabolism , Tachycardia, Ventricular/drug therapy , Mice , Male , Calcium Signaling/drug effects
6.
Biochem Biophys Res Commun ; 727: 150315, 2024 10 01.
Article in English | MEDLINE | ID: mdl-38950493

ABSTRACT

In response to mechanical loading of bone, osteocytes produce nitric oxide (NO•) and decrease sclerostin protein expression, leading to an increase in bone mass. However, it is unclear whether NO• production and sclerostin protein loss are mechanistically linked, and, if so, the nature of their hierarchical relationship within an established mechano-transduction pathway. Prior work showed that following fluid-shear stress (FSS), osteocytes produce NOX2-derived reactive oxygen species, inducing calcium (Ca2+) influx. Increased intracellular Ca2+ results in calcium-calmodulin dependent protein kinase II (CaMKII) activation, which regulates the lysosomal degradation of sclerostin protein. Here, we extend our discoveries, identifying NO• as a regulator of sclerostin degradation downstream of mechano-activated CaMKII. Pharmacological inhibition of nitric oxide synthase (NOS) activity in Ocy454 osteocyte-like cells prevented FSS-induced sclerostin protein loss. Conversely, short-term treatment with a NO• donor in Ocy454 cells or isolated murine long bones was sufficient to induce the rapid decrease in sclerostin protein abundance, independent of changes in Sost gene expression. Ocy454 cells express all three NOS genes, and transfection with siRNAs targeting eNOS/Nos3 was sufficient to prevent FSS-induced loss of sclerostin protein, while siRNAs targeting iNOS/Nos2 mildly blunted the loss of sclerostin but did not reach statistical significance. Similarly, siRNAs targeting both eNOS/Nos3 and iNOS/Nos2 prevented FSS-induced NO• production. Together, these data show iNOS/Nos2 and eNOS/Nos3 are the primary producers of FSS-dependent NO•, and that NO• is necessary and sufficient for sclerostin protein control. Further, selective inhibition of elements within this sclerostin-controlling mechano-transduction pathway indicated that NO• production occurs downstream of CaMKII activation. Targeting Camk2d and Camk2g with siRNA in Ocy454 cells prevented NO• production following FSS, indicating that CaMKII is needed for NO• production. However, NO• donation (1min) resulted in a significant increase in CaMKII activation, suggesting that NO• may have the ability to tune CaMKII response. Together, these data support that CaMKII is necessary for, and may be modulated by NO•, and that the interaction of these two signals is involved in the control of sclerostin protein abundance, consistent with a role in bone anabolic responses.


Subject(s)
Adaptor Proteins, Signal Transducing , Nitric Oxide , Osteocytes , Nitric Oxide/metabolism , Animals , Adaptor Proteins, Signal Transducing/metabolism , Adaptor Proteins, Signal Transducing/genetics , Osteocytes/metabolism , Mice , Stress, Mechanical , Mice, Inbred C57BL , Mechanotransduction, Cellular , Cell Line , Calcium-Calmodulin-Dependent Protein Kinase Type 2/metabolism
7.
PLoS Pathog ; 18(10): e1010882, 2022 10.
Article in English | MEDLINE | ID: mdl-36191037

ABSTRACT

COVID-19 vaccines are playing a vital role in controlling the COVID-19 pandemic. As SARS-CoV-2 variants encoding mutations in the surface glycoprotein, Spike, continue to emerge, there is increased need to identify immunogens and vaccination regimens that provide the broadest and most durable immune responses. We compared the magnitude and breadth of the neutralizing antibody response, as well as levels of Spike-reactive memory B cells, in individuals receiving a second dose of BNT162b2 at a short (3-4 week) or extended interval (8-12 weeks) and following a third vaccination approximately 6-8 months later. We show that whilst an extended interval between the first two vaccinations can greatly increase the breadth of the immune response and generate a higher proportion of Spike reactive memory B cells, a third vaccination leads to similar levels between the two groups. Furthermore, we show that the third vaccine dose enhances neutralization activity against omicron lineage members BA.1, BA.2 and BA.4/BA.5 and this is further increased following breakthrough infection during the UK omicron wave. These findings are relevant for vaccination strategies in populations where COVID-19 vaccine coverage remains low.


Subject(s)
COVID-19 , Viral Vaccines , Antibodies, Neutralizing , Antibodies, Viral , BNT162 Vaccine , COVID-19/prevention & control , COVID-19 Vaccines , Humans , Membrane Glycoproteins/genetics , Pandemics , SARS-CoV-2/genetics , Vaccination
8.
J Clin Gastroenterol ; 58(4): 389-401, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-37395627

ABSTRACT

INTRODUCTION: Clostridioides difficile infection (CDI) remains a global health challenge. Bezlotoxumab (BEZ) is a monoclonal antibody against C. difficile toxin B. Two randomized controlled trials (RCTs), MODIFY I and II, confirmed BEZ efficacy in preventing recurrent Clostridioides difficile infection (rCDI). However, there are safety concerns about its use in patients with a history of congestive heart failure. Observational studies have since been conducted, and it is important to explore the consistency of BEZ efficacy, cost-effectiveness, and its safety utilizing these real-world data. METHODS: We performed a systematic review and meta-analysis to pool the rate of rCDI in patients receiving BEZ and explore its efficacy and safety in preventing rCDI compared with control. We searched PubMed, EMBASE, Cochrane Library, and Google Scholar from inception through April 2023 for relevant RCTs or observational studies assessing BEZ in preventing rCDI. Single-arm studies describing experience with BEZ in preventing rCDI were also included for proportion meta-analysis. A proportion meta-analysis with a random-effects model was used to pool the rCDI rate with its corresponding 95% CI. In a meta-analysis of efficacy, we generated the relative risk (RR) to compare BEZ versus control in preventing rCDI. RESULTS: Thirteen studies including 2 RCTs and 11 observational studies totaling 2337 patients, of which 1472 received BEZ, were included in the analysis. Of the constituent studies, 5 (1734 patients) compared BEZ versus standard-of-care (SOC). Pooled rate of rCDI in patients receiving BEZ was 15.8% (95% CI: 14%-17.8%), and was 28.9% (95% CI: 24%-34.4%) in the SOC. BEZ significantly reduced rCDI risk compared with SOC [RR=0.57 (95% CI: 0.45-0.72, I2 =16%)]. There was no difference in the overall mortality or heart failure risk. Of the 9 included cost-effectiveness analyses, 8 demonstrated BEZ+SOC cost-effectiveness compared with SOC alone. DISCUSSION: Our meta-analysis comprising real-world data revealed lower rCDI in patients receiving BEZ and supported its efficacy and safety when added to SOC therapy. The results were consistent across various subgroups. Available cost-effectiveness analyses mostly support BEZ+SOC cost-effectiveness compared with SOC alone.


Subject(s)
Broadly Neutralizing Antibodies , Clostridioides difficile , Clostridium Infections , Humans , Anti-Bacterial Agents/adverse effects , Cost-Benefit Analysis , Recurrence , Antibodies, Monoclonal/adverse effects
9.
Ann Fam Med ; 21(Suppl 3)2024 Nov 01.
Article in English | MEDLINE | ID: mdl-38271180

ABSTRACT

Context: The present study builds on our prior work that demonstrated an association between pharmacogenetic interactions and 90-day readmission. Objective: Evaluate aggregate contribution of social determinants, comorbidity, and gene-x-drug interactions to moderate 90-day hospital readmission. Study Design and Analysis: Non-concurrent cohort study; Multivariable logistic regression Setting: Hospital/integrated healthcare delivery system in northern Illinois Population Studied: 19,999 adults tracked from 2010 through 2020 who underwent testing with a 13-gene pharmacogenetic panel Outcome Measure: 90-day hospital readmission (primary outcome) Results: Univariate logistic regression analyses demonstrated that strongest associations with 90 day hospital readmissions were the number of medications prescribed within 30 days of a first hospital admission that had Clinical Pharmacogenomics Implementation Consortium (CPIC) guidance (CPIC medications) (5+ CPIC medications, odds ratio (OR) = 7.66, 95% confidence interval 5.45-10.77) (p < 0.0001), major comorbidities (5+ comorbidities, OR 3.36, 2.61-4.32) (p < 0.0001), age (65 + years, OR = 2.35, 1.77-3.12) (p < 0.0001), unemployment (OR = 2.19, 1.88-2.64) (p < 0.0001), Black/African-American race (OR 2.12, 1.47-3.07) (p < 0.0001), median household income (OR = 1.63, 1.03-2.58) (p = 0.035), male gender (OR = 1.47, 1.21-1.80) (p = 0.0001), and one or more gene-x-drug interaction (defined as a prescribed CPIC medication for a patient with a corresponding actionable pharmacogenetic variant) (OR = 1.41, 1.18-1.70). Health insurance was not associated with risk of 90-day readmission. Race, income, employment status, and gene-x-drug interactions were robust in a multivariable logistic regression model. The odds of 90-day readmission for patients with one or more identified gene-x-drug interactions after adjustment for these covariates was attenuated by 10% (OR = 1.31, 1.08-1.59) (p = 0.006). Although the interaction between race and gene-x-drug interactions was not statistically significant, White patients were more likely to have a gene-x-drug interaction (35.2%) than Black/African-American patients (25.9%) who were not readmitted (p < 0.0001). Conclusions: These results highlight the major contribution of social determinants and medical complexity to risk for hospital readmission, and that these determinants may modify the effect of gene-x-drug interactions on rehospitalization risk.


Subject(s)
Patient Readmission , Pharmacogenetics , Adult , Humans , Male , United States , Aged , Cohort Studies , Social Determinants of Health , Retrospective Studies , Risk Factors , Drug Interactions
10.
J Am Acad Dermatol ; 91(2): 290-299, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38604489

ABSTRACT

BACKGROUND: Epidermolysis bullosa (EB), characterized by skin fragility and blistering, often requires hospitalization. Training for inpatient management of EB is limited, with no unified recommendations available in North America. OBJECTIVE: To develop consensus-derived best practices for hands-on inpatient management of EB in both the neonatal and postneonatal period. METHODS: A modified Delphi method (expert-based input via 2 surveys and a final review) was implemented. Available guidelines from EB Clinical Research Consortium centers were analyzed to determine areas of focus and formulate statements to be voted on by EB Clinical Research Consortium members, experienced EB nurses, and select family members. Study participants evaluated statements using a Likert scale: statements with at least 70% agreement were accepted; statements with 30% or more disagreement were rejected. RESULTS: Ten areas of focus were identified. Delphi participants included 15 dermatologists, 8 nurses, and 6 nonhealth care caregivers. Consensus was established on 103/119 neonatal statements and 105/122 postneonatal statements; no statements were rejected. Most recommendations applied to both age groups. LIMITATIONS: Recommendations may require adjustment based on individual patient's clinical context. CONCLUSION: Using the Delphi method, a consensus-derived resource for hospital-based health care professionals who manage patients with EB has been developed to improve the quality of inpatient care.


Subject(s)
Consensus , Delphi Technique , Epidermolysis Bullosa , Humans , Infant, Newborn , Epidermolysis Bullosa/therapy , Hospitalization , Practice Guidelines as Topic , Infant , Female , Dermatology/methods , Dermatology/standards , Male
11.
Br J Anaesth ; 2024 Oct 10.
Article in English | MEDLINE | ID: mdl-39389833

ABSTRACT

BACKGROUND: Nitrous oxide (N2O) is a potent greenhouse gas that contributes significantly to the healthcare sector's carbon footprint. Pre-utilisation losses of N2O are up to 95%. Decommissioning manifolds can reduce these losses. METHODS: Hospitals in our Greater London research network with at least one active N2O manifold were included in the Nitrous Oxide Manifold and Other Reduction of Emissions (NoMoreGas) study. N2O utilisation data were collected continuously over 5 days and extrapolated over a year, in addition to collecting procurement records from the preceding financial year. The primary outcome was the discrepancy between clinically utilised N2O and the quantity procured by hospitals, referred to as the 'N2O gap'. Secondary outcomes included anaesthetists' self-reported utilisation of N2O and their opinions on manifold decommissioning. RESULTS: Eighteen of 53 hospitals were included. In total, 6 487 200 L of N2O were procured with a median (IQR) of 304 200 (183 600-473 400) L per site. During the 5-day data collection period, sites utilised a median (IQR) of 501 (42-1409) L of N2O. Extrapolating over a year resulted in a median (IQR) annual utilisation of 36 573 (3066-102 857) L per site and a total of 1 175 348 L. This represented an estimated 18% of the N2O procured, suggesting pre-utilisation losses of 5 311 852 L. Among surveyed anaesthetists, 70% (n=309) reported using N2O within the previous year, with one-third (n=97) using it once a week or more. There was widespread support for decommissioning manifolds. CONCLUSIONS: Consistent with other reports, the data demonstrate a substantial discrepancy between the quantities of N2O procured and utilised clinically, indicative of significant pre-utilisation losses. Our findings support the decommissioning of N2O manifolds for environmental and economic benefits.

12.
J Physiol ; 601(21): 4767-4806, 2023 11.
Article in English | MEDLINE | ID: mdl-37786382

ABSTRACT

Comprehensive and accurate analysis of respiratory and metabolic data is crucial to modelling congenital, pathogenic and degenerative diseases converging on autonomic control failure. A lack of tools for high-throughput analysis of respiratory datasets remains a major challenge. We present Breathe Easy, a novel open-source pipeline for processing raw recordings and associated metadata into operative outcomes, publication-worthy graphs and robust statistical analyses including QQ and residual plots for assumption queries and data transformations. This pipeline uses a facile graphical user interface for uploading data files, setting waveform feature thresholds and defining experimental variables. Breathe Easy was validated against manual selection by experts, which represents the current standard in the field. We demonstrate Breathe Easy's utility by examining a 2-year longitudinal study of an Alzheimer's disease mouse model to assess contributions of forebrain pathology in disordered breathing. Whole body plethysmography has become an important experimental outcome measure for a variety of diseases with primary and secondary respiratory indications. Respiratory dysfunction, while not an initial symptom in many of these disorders, often drives disability or death in patient outcomes. Breathe Easy provides an open-source respiratory analysis tool for all respiratory datasets and represents a necessary improvement upon current analytical methods in the field. KEY POINTS: Respiratory dysfunction is a common endpoint for disability and mortality in many disorders throughout life. Whole body plethysmography in rodents represents a high face-value method for measuring respiratory outcomes in rodent models of these diseases and disorders. Analysis of key respiratory variables remains hindered by manual annotation and analysis that leads to low throughput results that often exclude a majority of the recorded data. Here we present a software suite, Breathe Easy, that automates the process of data selection from raw recordings derived from plethysmography experiments and the analysis of these data into operative outcomes and publication-worthy graphs with statistics. We validate Breathe Easy with a terabyte-scale Alzheimer's dataset that examines the effects of forebrain pathology on respiratory function over 2 years of degeneration.


Subject(s)
Respiration , Software , Animals , Mice , Humans , Longitudinal Studies , Plethysmography
13.
Mamm Genome ; 34(2): 180-199, 2023 06.
Article in English | MEDLINE | ID: mdl-37294348

ABSTRACT

Reference ranges provide a powerful tool for diagnostic decision-making in clinical medicine and are enormously valuable for understanding normality in pre-clinical scientific research that uses in vivo models. As yet, there are no published reference ranges for electrocardiography (ECG) in the laboratory mouse. The first mouse-specific reference ranges for the assessment of electrical conduction are reported herein generated from an ECG dataset of unprecedented scale. International Mouse Phenotyping Consortium data from over 26,000 conscious or anesthetized C57BL/6N wildtype control mice were stratified by sex and age to develop robust ECG reference ranges. Interesting findings include that heart rate and key elements from the ECG waveform (RR-, PR-, ST-, QT-interval, QT corrected, and QRS complex) demonstrate minimal sexual dimorphism. As expected, anesthesia induces a decrease in heart rate and was shown for both inhalation (isoflurane) and injectable (tribromoethanol) anesthesia. In the absence of pharmacological, environmental, or genetic challenges, we did not observe major age-related ECG changes in C57BL/6N-inbred mice as the differences in the reference ranges of 12-week-old compared to 62-week-old mice were negligible. The generalizability of the C57BL/6N substrain reference ranges was demonstrated by comparison with ECG data from a wide range of non-IMPC studies. The close overlap in data from a wide range of mouse strains suggests that the C57BL/6N-based reference ranges can be used as a robust and comprehensive indicator of normality. We report a unique ECG reference resource of fundamental importance for any experimental study of cardiac function in mice.


Subject(s)
Electrocardiography , Electrophysiologic Techniques, Cardiac , Mice , Animals , Mice, Inbred C57BL , Mice, Inbred Strains
14.
PLoS Pathog ; 17(4): e1009417, 2021 04.
Article in English | MEDLINE | ID: mdl-33861800

ABSTRACT

Macrophages are important drivers of pathogenesis and progression to AIDS in HIV infection. The virus in the later phases of the infection is often predominantly macrophage-tropic and this tropism contributes to a chronic inflammatory and immune activation state that is observed in HIV patients. Pattern recognition receptors of the innate immune system are the key molecules that recognise HIV and mount the inflammatory responses in macrophages. The innate immune response against HIV-1 is potent and elicits caspase-1-dependent pro-inflammatory cytokine production of IL-1ß and IL-18. Although, NLRP3 has been reported as an inflammasome sensor dictating this response little is known about the pattern recognition receptors that trigger the "priming" signal for inflammasome activation, the NLRs involved or the HIV components that trigger the response. Using a combination of siRNA knockdowns in monocyte derived macrophages (MDMs) of different TLRs and NLRs as well as chemical inhibition, it was demonstrated that HIV Vpu could trigger inflammasome activation via TLR4/NLRP3 leading to IL-1ß/IL-18 secretion. The priming signal is triggered via TLR4, whereas the activation signal is triggered by direct effects on Kv1.3 channels, causing K+ efflux. In contrast, HIV gp41 could trigger IL-18 production via NAIP/NLRC4, independently of priming, as a one-step inflammasome activation. NAIP binds directly to the cytoplasmic tail of HIV envelope protein gp41 and represents the first non-bacterial ligand for the NAIP/NLRC4 inflammasome. These divergent pathways represent novel targets to resolve specific inflammatory pathologies associated with HIV-1 infection in macrophages.


Subject(s)
HIV Infections/virology , Inflammasomes/immunology , Interleukin-18/metabolism , Interleukin-1beta/metabolism , Macrophages/virology , Peptide Fragments/metabolism , Cell Communication/genetics , Cell Communication/immunology , Gene Expression/genetics , Gene Expression/immunology , HIV Infections/metabolism , Humans , Immunity, Innate/genetics , Immunity, Innate/immunology , Inflammasomes/metabolism , Macrophages/immunology , Neuronal Apoptosis-Inhibitory Protein/genetics , Signal Transduction/immunology
15.
Int J Hyperthermia ; 40(1): 2159072, 2023.
Article in English | MEDLINE | ID: mdl-36581324

ABSTRACT

OBJECTIVE: To investigate the effect of bidirectional fecal microbial transplant (FMT) between male and female rats on methamphetamine (MA)-induced hyperthermia. METHODS: FMT was performed between male and female rats prior to MA (10 mg/kg, sc) treatment. Core body temperature, plasma drug and norepinephrine (NE) levels were measured and compared between treatment groups. 16S rRNA gene sequencing of bacterial communities between male and female rats was performed. RESULTS: MA treatment resulted in significantly higher core body temperatures in male groups (control and FMT-treated) compared to MA-treated female groups (control and FMT-treated). Plasma concentrations of MA and amphetamine were higher in females than males. Whereas, plasma norepinephrine (NE) levels were not different between male and female rats 90 minutes after MA treatment. At the phyla level, the microbiome of male and female control rats were dominated by Firmicutes and Bacteroidetes. Males had a higher relative abundance of Firmicutes and lower relative abundances of Bacteroidetes than females. The FMT procedure changed the recipient group towards their donor with males getting closer to their donors than females. In the control groups following MA treatment, Firmicutes increased and Bacteroides decreased in females and males. Conversely, in the FMT treatment groups following MA treatment, Firmicutes decreased while Bacteroidetes increased in females and males. CONCLUSIONS: Although definite differences in the structure and diversity of the gut microbiome were observed using 16S rRNA gene sequencing of bacterial communities between male and female rats, these differences do not seem to contribute to the sex-based differences in MA-induced hyperthermia.


Subject(s)
Clostridium Infections , Hyperthermia, Induced , Methamphetamine , Male , Female , Rats , Animals , Feces/microbiology , RNA, Ribosomal, 16S/genetics , Clostridium Infections/microbiology , Clostridium Infections/therapy , Bacteria
16.
Intern Med J ; 53(12): 2162-2174, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37528613

ABSTRACT

Haematopoietic stem cell transplantation is a mainstay of therapy for numerous malignant and nonmalignant diseases. Endothelial activation and dysfunction occur after stem cell transplantation, driven by various patient- and transplant-specific factors. This can manifest as one of the relatively uncommon endothelial injury syndromes, such as sinusoidal obstruction syndrome, transplant-associated thrombotic microangiopathy, idiopathic pneumonia syndrome, capillary leak syndrome, engraftment syndrome or posterior reversible encephalopathy syndrome. This review focuses on the pathogenesis, classification and diagnosis of these disorders, as well as provides guidance on risk mitigation and treatment.


Subject(s)
Hematologic Diseases , Hematopoietic Stem Cell Transplantation , Pneumonia , Posterior Leukoencephalopathy Syndrome , Thrombotic Microangiopathies , Humans , Posterior Leukoencephalopathy Syndrome/complications , Hematopoietic Stem Cell Transplantation/adverse effects , Thrombotic Microangiopathies/diagnosis , Thrombotic Microangiopathies/etiology , Thrombotic Microangiopathies/therapy
17.
Intern Med J ; 53(4): 599-609, 2023 04.
Article in English | MEDLINE | ID: mdl-36441109

ABSTRACT

Waldenström macroglobulinaemia (WM) is an indolent B-cell malignancy characterised by the presence of IgM paraprotein, bone marrow infiltration by clonal small B lymphocytes with plasmacytic differentiation and the MYD88 L265P mutation in >90% of cases. Traditionally, WM has been treated with chemoimmunotherapy. Recent trials have demonstrated the efficacy and safety of Bruton tyrosine kinase inhibitors in WM, both as monotherapy and in combination with other drugs. There is emerging evidence on the use of other agents including B-cell lymphoma 2 inhibitors and on the treatment of rare presentations of WM. In this update, the Medical and Scientific Advisory Group of Myeloma Australia reviews the available evidence on the treatment of WM since the last publication in 2017 and provides specific recommendations to assist Australian clinicians in the management of this disease.


Subject(s)
Antineoplastic Agents , Multiple Myeloma , Waldenstrom Macroglobulinemia , Humans , Waldenstrom Macroglobulinemia/diagnosis , Waldenstrom Macroglobulinemia/drug therapy , Waldenstrom Macroglobulinemia/genetics , Multiple Myeloma/drug therapy , Australia/epidemiology , Antineoplastic Agents/therapeutic use , Bone Marrow/pathology , Mutation , Myeloid Differentiation Factor 88/genetics
18.
Intern Med J ; 53(5): 819-824, 2023 05.
Article in English | MEDLINE | ID: mdl-36880355

ABSTRACT

Multiple myeloma (MM) is a disease of older people, yet factors relating to comorbidity and frailty may threaten treatment tolerability for many of this heterogenous group. There has been increasing interest in defining specific and clinically relevant frailty assessment tools within the MM population, with the goal of using these frailty scores, not just as a prognostic instrument, but also as a predictive tool to allow for a frailty-adapted treatment approach. This paper reviews the various frailty assessment frameworks used in the evaluation of patients with MM, including the International Myeloma Working Group Frailty Index (IMWG-FI), the Mayo Frailty Index and the simplified frailty scale. While the IMWG-FI remains the most widely accepted tool, the simplified frailty scale is the most user-friendly in busy day-to-day clinics based on its ease of use. This paper summarises the recommendations from the Myeloma Scientific Advisory Group (MSAG) of Myeloma Australia, on the use of frailty assessment tools in clinical practice and proposes a frailty-stratified treatment algorithm to aid clinicians in tailoring therapy for this highly heterogeneous patient population.


Subject(s)
Frailty , Multiple Myeloma , Humans , Aged , Frailty/epidemiology , Multiple Myeloma/drug therapy , Frail Elderly , Prognosis , Comorbidity , Geriatric Assessment
19.
BMC Pulm Med ; 23(1): 341, 2023 Sep 12.
Article in English | MEDLINE | ID: mdl-37697259

ABSTRACT

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) lung infection has represented a global challenge. Intriguingly, it has been shown that the alveolar lung epithelium expresses little Angiotensin Converting Enzyme receptor protein (ACE2), the entry receptor for SARS-CoV-2. Upper airway establishment of infection and translocation to the lung is well documented but other anatomical niches may be relevant to potentially serious lung infection. ACE2 is heavily expressed in the gastrointestinal tract and gastrointestinal symptoms support a clinical diagnosis of Coronavirus disease 2019 (COVID-19). This suggests a research question and the need to gather patient data exploring potential aerodigestive links in SARS-CoV-2 tranlocation and infection which may be relevant in the peripheral lung. This recognizes anatomical proximity and concepts of bi-directional movement between the Gastrointestinal and lung systems in normal physiology and disease. We have therefore explored the potential for gastro oesophageal reflux disease (GORD) micro aspiration and aeorodigestive pathophysiology in a novel prospective investigation of patients hospitalized with COVID-19. METHODS: This is a prospective descriptive cohort study of 210 patients who were hospitalized with a confirmed diagnosis of COVID-19. The cohort was divided into three groups of patients based on symptom severity and radiological results. The Reflux Symptom Index (RSI) was used to evaluate the presence and severity of GOR. An RSI greater than 13 is considered to be abnormal. Patients' saliva samples were tested using enzyme-linked immunosorbent assay (ELISA) to determine the level of salivary pepsin among the cohort of patients. RESULTS: A total of 210 patients with COVID-19 were enrolled in the study with 55.2% (116/210) classified as mildly ill, 31.9% (67/210) moderately ill and 12.9% (27/210) as severely ill. 34% (72/210) of the patients had an RSI score of over 13 and a median salivary pepsin value of 54 ± 29 ng/ml which suggested an incidence of extraesophageal reflux (EOR) in around a third of patients. The presence of respiratory comorbid conditions, an RSI score of over 13 and a salivary pepsin level of > 76ng/ml increased the risk of developing a more severe COVID-19 infection. CONCLUSION: The study showed a high prevalence of EOR among the study cohort and provide the first prospective evidence suggesting the potential for aerodigestive pathophysiology including microaspiration in COVID-19 disease. We believe that the results of our study support the need for more extensive research.


Subject(s)
COVID-19 , Gastroesophageal Reflux , Humans , COVID-19/epidemiology , Prospective Studies , SARS-CoV-2 , Jordan/epidemiology , Angiotensin-Converting Enzyme 2 , Cohort Studies , Pepsin A , Gastroesophageal Reflux/epidemiology
20.
Proc Natl Acad Sci U S A ; 117(42): 26008-26019, 2020 10 20.
Article in English | MEDLINE | ID: mdl-33020304

ABSTRACT

Changes in the mechanical microenvironment and mechanical signals are observed during tumor progression, malignant transformation, and metastasis. In this context, understanding the molecular details of mechanotransduction signaling may provide unique therapeutic targets. Here, we report that normal breast epithelial cells are mechanically sensitive, responding to transient mechanical stimuli through a two-part calcium signaling mechanism. We observed an immediate, robust rise in intracellular calcium (within seconds) followed by a persistent extracellular calcium influx (up to 30 min). This persistent calcium was sustained via microtubule-dependent mechanoactivation of NADPH oxidase 2 (NOX2)-generated reactive oxygen species (ROS), which acted on transient receptor potential cation channel subfamily M member 8 (TRPM8) channels to prolong calcium signaling. In contrast, the introduction of a constitutively active oncogenic KRas mutation inhibited the magnitude of initial calcium signaling and severely blunted persistent calcium influx. The identification that oncogenic KRas suppresses mechanically-induced calcium at the level of ROS provides a mechanism for how KRas could alter cell responses to tumor microenvironment mechanics and may reveal chemotherapeutic targets for cancer. Moreover, we find that expression changes in both NOX2 and TRPM8 mRNA predict poor clinical outcome in estrogen receptor (ER)-negative breast cancer patients, a population with limited available treatment options. The clinical and mechanistic data demonstrating disruption of this mechanically-activated calcium pathway in breast cancer patients and by KRas activation reveal signaling alterations that could influence cancer cell responses to the tumor mechanical microenvironment and impact patient survival.


Subject(s)
Breast/pathology , Calcium/metabolism , Mechanotransduction, Cellular , NADPH Oxidase 2/metabolism , Proto-Oncogene Proteins p21(ras)/metabolism , Reactive Oxygen Species/metabolism , TRPM Cation Channels/metabolism , Breast/metabolism , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Cell Transformation, Neoplastic/metabolism , Cell Transformation, Neoplastic/pathology , Cells, Cultured , Epithelial Cells/metabolism , Epithelial Cells/pathology , Female , Humans , Microtubules/metabolism , NADPH Oxidase 2/genetics , Prognosis , Proto-Oncogene Proteins p21(ras)/genetics , Survival Rate , TRPM Cation Channels/genetics , Tumor Microenvironment
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