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1.
bioRxiv ; 2024 Jul 30.
Article in English | MEDLINE | ID: mdl-39109178

ABSTRACT

The continued evolution of SARS-CoV-2 variants capable of subverting vaccine and infection-induced immunity suggests the advantage of a broadly protective vaccine against betacoronaviruses (ß-CoVs). Recent studies have isolated monoclonal antibodies (mAbs) from SARS-CoV-2 recovered-vaccinated donors capable of neutralizing many variants of SARS-CoV-2 and other ß-CoVs. Many of these mAbs target the conserved S2 stem region of the SARS-CoV-2 spike protein, rather the receptor binding domain contained within S1 primarily targeted by current SARS-CoV-2 vaccines. One of these S2-directed mAbs, CC40.8, has demonstrated protective efficacy in small animal models against SARS-CoV-2 challenge. As the next step in the pre-clinical testing of S2-directed antibodies as a strategy to protect from SARS-CoV-2 infection, we evaluated the in vivo efficacy of CC40.8 in a clinically relevant non-human primate model by conducting passive antibody transfer to rhesus macaques (RM) followed by SARS-CoV-2 challenge. CC40.8 mAb was intravenously infused at 10mg/kg, 1mg/kg, or 0.1 mg/kg into groups (n=6) of RM, alongside one group that received a control antibody (PGT121). Viral loads in the lower airway were significantly reduced in animals receiving higher doses of CC40.8. We observed a significant reduction in inflammatory cytokines and macrophages within the lower airway of animals infused with 10mg/kg and 1mg/kg doses of CC40.8. Viral genome sequencing demonstrated a lack of escape mutations in the CC40.8 epitope. Collectively, these data demonstrate the protective efficiency of broadly neutralizing S2-targeting antibodies against SARS-CoV-2 infection within the lower airway while providing critical preclinical work necessary for the development of pan-ß-CoV vaccines.

2.
Chem Sci ; 2024 Aug 20.
Article in English | MEDLINE | ID: mdl-39176248

ABSTRACT

Nature has endowed us with some complex enzymes capable of utilizing proteins as their substrates to generate functional proteins through post-translational modification. However, nanozymes' interplay with proteins as substrates is scarce, with their chemistry predominantly established using only small molecule substrates, featuring a significant gap in this area. Due to the huge prospects of nanozymes in biotechnological and therapeutic interventions, studies establishing the unexplored roles of nanozymes in the biological environments and their interplay beyond small molecule substrates warrant immediate attention. In this study, we unveil the unprecedented role of a Mn-based oxidase nanozyme (MnN) in activating a structural protein, collagen, and covalently crosslinking its tyrosine residues with only a trace amount of tannic acid (TA) without compromising its triple-helical structural integrity. While therapeutic applications demand materials prepared from collagen, the current chemical and physical crosslinking of collagen often presents significant challenges such as toxicity, denaturation, or high costs. MnN lucidly accomplishes crosslinking interplay at its 101 facets using oxygen as a co-substrate under mild conditions. This process takes advantage of MnN being active at mild acidic pH where collagen preferentially exists as a soluble triple helix (monomeric form), exposing functionalities and enhancing the crosslinking degree. Importantly, this reaction also confers 100% resistance to collagenase attack on the collagen tendon-derived biological material. The catalyzed TA-tyrosine linkage in the telopeptide region of collagen probably impedes the initial recognition step of collagenase, providing robust protection against its degradative action. Our study not only expands the repertoire of nanozymes' substrates beyond the existing library of small molecules but also establishes a significant step toward designing a gold standard for collagen crosslinking. With biomedical applications demanding biomaterials derived from protein scaffolds with preserved structural integrity, our investigation bridges the gap between nanozymes' chemistry and crosslinking proteins, opening exciting prospects for biomaterial development.

3.
Int Immunopharmacol ; 142(Pt A): 113029, 2024 Aug 30.
Article in English | MEDLINE | ID: mdl-39216116

ABSTRACT

Autoimmune hemolytic anemia (AIHA) is a heterogeneous group of diseases mediated by autoantibody directed against RBCs causing hemolysis and anemia. AIHA develops rapidly or over time, depending on the triggering factor. Desidustat is a prolyl hydroxylase inhibitor clinically used for the treatment of chronic kidney disease (CKD)-induced anemia. In this study, we investigated the effect of desidustat in preclinical model of AIHA. We used rat RBC for induction of AIHA in mice. These mice were then treated with desidustat (15 mg/kg, PO, once a day) for eight weeks. Desidustat treatment increased hemoglobin, RBC and hematocrit and decreased WBC and lymphocytes. This treatment suppressed serum LDH, oxidative stress in RBCs, antibody titer and antibody deposition on RBC surface, and increased RBC lifespan. Serum and spleen iron along with spleen mass and oxidative stress were decreased by desidustat. Bone marrow iron was increased and expression of CD71 (cell surface marker for early erythroid progenitor) and TER-119 (cell surface marker for late erythroid progenitor) in bone marrow were found to be elevated by desidustat by treatment. This treatment also suppressed deposition of membrane-bound antibody in late erythroid cells. The treatment showed reduction in total splenic cells, CD71 and TER-119 positive cells in the spleen. Thus, desidustat treatment increased erythropoiesis, early maturation of bone marrow erythroid cells having longer RBC life span due to decrease in the antibody-mediated lysis of RBCs and its progenitors leading to reduced oxidative stress. Thus, desidustat can be a good therapeutic option for treatment of AIHA.

4.
Chem Sci ; 15(28): 10810-10822, 2024 Jul 17.
Article in English | MEDLINE | ID: mdl-39027301

ABSTRACT

Advances in nanozymes have taken shape over the past few years in several domains. However, persisting challenging limitations of selectivity, specificity, and efficiency necessitate careful attention to aid in the development of next-generation artificial enzymes. Despite nanozymes having significant therapeutic and biotechnological prospects, the multienzyme mimetic activities can compromise their intended applications. Furthermore, the lack of substrate selectivity can hamper crucial biological pathways. While working on addressing the challenges of nanozymes, in this work, we aim to highlight the interplay between the substrates and bis-(µ-oxo) dicopper active site-installed MOF-808 for selectively mimicking oxidase. This oxidase mimetic with a small pore-aperture (1.4 nm), similar to the opening of enzyme binding pockets, projects a tight control over the dynamics and the reactivity of substrates, making it distinct from the general oxidase nanozymes. Interestingly, the design and the well-regulated activity of this nanozyme effectively thwart DNA from approaching the active site, thereby preventing its oxidative damage. Crucially, we also show that despite these merits, the oxidase selectivity is compromised by small proteins such as cytochrome c (Cyt c), having dimensions larger than the pore aperture of MOF-808. This reaction lucidly produces water molecules as a result of four electron transfer to an oxygen molecule. Such unintended side reactivities warrant special attention as they can perturb redox processes and several cellular energy pathways. Through this study, we provide a close look at designing next-generation artificial enzymes that can address the complex challenges for their utility in advanced applications.

5.
J Assoc Physicians India ; 72(7): 68-72, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38990590

ABSTRACT

The management of edema requires a systematic approach to screening, diagnosis, and treatment, with an essential initial assessment to differentiate between generalized and localized edema. The Association of Physicians of India (API) aimed to develop the first Indian Edema Consensus (Edema India), offering tailored recommendations for screening, diagnosing, and managing edema based on the insights from the expert panel. The panel suggested when evaluating edema symptoms, important factors to consider include the patient's current illness, medical history, risk factors, family history, and medications. Key diagnostic investigations for edema include complete blood count, cardiovascular imaging and markers, deep vein thrombosis (DVT) assessment, along with renal, hepatic, and thyroid function tests. Edema management involves a combination of pharmacologic and nonpharmacologic interventions, including limb elevation, physiotherapy, compression therapy, fluid removal, diuretics (loop diuretics: first-line therapy), and a sodium-restricted diet. The panel believed that educating patients could foster a preventive mindset, helping to prevent the worsening of edema.


Subject(s)
Edema , Humans , Edema/therapy , Edema/diagnosis , Edema/etiology , India
6.
Drug Res (Stuttg) ; 74(7): 325-334, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38991528

ABSTRACT

Complement cascade is a defence mechanism useful for eliminating pathogenic microorganisms and damaged cells. However, activation of alternative complement system can also cause inflammation and promote kidney and retinal disease progression. Inflammation causes tissue hypoxia, which induces hypoxia-inducible factor (HIF) and HIF helps the body to adapt to inflammation. In this study, we investigated the effect of HIF stabilizer desidustat in complement-mediated diseases. Oral administration of desidustat (15 mg/kg) was effective to reduce the kidney injury in mice that was induced by either lipopolysaccharide (LPS), doxorubicin or bovine serum albumin (BSA)-overload. Complement activation-induced membrane attack complex (MAC) formation and factor B activity were also reduced by desidustat treatment. In addition, desidustat was effective against membranous nephropathy caused by cationic BSA and retinal degeneration induced by sodium iodate in mice. C3-deposition, proteinuria, malondialdehyde, and interleukin-1ß were decreased and superoxide dismutase was increased by desidustat treatment in cBSA-induced membranous nephropathy. Desidustat specifically inhibited alternative complement system, without affecting the lectin-, or classical complement pathway. This effect appears to be mediated by inhibition of factor B. These data demonstrate the potential therapeutic value of HIF stabilization by desidustat in treatment of complement-mediated diseases.


Subject(s)
Complement Activation , Animals , Mice , Complement Activation/drug effects , Glomerulonephritis, Membranous/drug therapy , Glomerulonephritis, Membranous/metabolism , Glomerulonephritis, Membranous/pathology , Male , Lipopolysaccharides , Retinal Degeneration/drug therapy , Retinal Degeneration/prevention & control , Retinal Degeneration/metabolism , Retinal Degeneration/pathology , Serum Albumin, Bovine , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Complement Membrane Attack Complex/metabolism , Disease Models, Animal , Kidney/drug effects , Kidney/metabolism , Kidney/pathology , Interleukin-1beta/metabolism , Protective Agents/pharmacology
7.
Maturitas ; 187: 108044, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38885594

ABSTRACT

For women under age 65, varying recommendations and the need to apply clinical risk calculators can lead to underscreening for osteoporosis. The resulting undertreatment may lead to a risk of osteoporotic fractures with significant morbidity and impact on functional status. Factors that must be considered when deciding to screen a woman under age 65 include a history of fragility fractures, race, family history, body mass index, smoking, high alcohol use, and secondary causes of osteoporosis. Secondary causes of osteoporosis are much more common in younger women. These include common conditions such as glucocorticoid use, hyperthyroidism, hypogonadism, chronic kidney disease, diabetes, anticonvulsant use, rheumatoid arthritis, malabsorption, and a history of anorexia nervosa. The reasons why these conditions confer an increased risk of osteoporosis are discussed. Recommendations are provided for the clinician to be aware of when screening women under age 65 for osteoporosis and initiating treatment when indicated.


Subject(s)
Osteoporosis , Osteoporotic Fractures , Humans , Female , Osteoporosis/diagnosis , Osteoporosis/etiology , Osteoporotic Fractures/prevention & control , Osteoporotic Fractures/etiology , Middle Aged , Mass Screening/methods , Risk Factors , Age Factors , Osteoporosis, Postmenopausal
8.
Bioorg Med Chem ; 109: 117796, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-38879996

ABSTRACT

The USFDA granted regular approval to Osimertinib (AZD9291) on March 2017, for treating individuals with metastatic Non-Small Cell Lung Cancer having EGFR T790M mutation. Clinically, Osimertinib stands at the forefront for the treatment of patients with Non-Small Cell Lung Cancer. Osimertinib forms a covalent bond with the Cys797 residue and predominantly spares binding to WT-EGFR, thereby reducing toxicity and enabling the administration of doses that effectively inhibit T790M. However, a high percentage of patients treated with Osimertinib (AZD9291) developed a tertiary cysteine797 to serine797 (C797S) mutation in the EGFR kinase domain, rendering resistance to it. This comprehensive review sheds light on the chemistry, computational aspects, structural features, and expansive spectrum of biological activities of Osimertinib and its analogues. The in-depth exploration of these facets serves as a valuable resource for medicinal chemists, empowering them to design better Osimertinib analogues. This exhaustive study not only provides insights into improving potency but also emphasizes considerations for mutant selectivity and optimizing pharmacokinetic properties. This review acts as a guiding beacon for the strategic design and development of next-generation Osimertinib analogues.


Subject(s)
Acrylamides , Aniline Compounds , Antineoplastic Agents , Carcinoma, Non-Small-Cell Lung , ErbB Receptors , Lung Neoplasms , Mutation , Protein Kinase Inhibitors , Acrylamides/chemistry , Acrylamides/pharmacology , Aniline Compounds/chemistry , Aniline Compounds/pharmacology , Humans , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/pathology , ErbB Receptors/antagonists & inhibitors , ErbB Receptors/metabolism , ErbB Receptors/genetics , Lung Neoplasms/drug therapy , Lung Neoplasms/pathology , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/chemical synthesis , Structure-Activity Relationship , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemical synthesis , Molecular Structure , Piperazines/chemistry , Piperazines/pharmacology , Indoles , Pyrimidines
9.
PLoS Pathog ; 20(5): e1012223, 2024 May.
Article in English | MEDLINE | ID: mdl-38739675

ABSTRACT

Natural killer-like B (NKB) cells are unique innate immune cells expressing both natural killer (NK) and B cell receptors. As first responders to infection, they secrete IL-18 to induce a critical cascade of innate and adaptive immune cell infiltration and activation. However, limited research exists on the role of NKB cells in homeostasis and infection, largely due to incomplete and erroneous evaluations. To fill this knowledge gap, we investigated the expression of signaling and trafficking proteins, and the in situ localization and transcriptome of naïve NKB cells compared to conventionally-defined NK and B cells, as well as modulations of these cells in SIV infection. Intracellular signaling proteins and trafficking markers were expressed differentially on naïve NKB cells, with high expression of CD62L and Syk, and low expression of CD69, α4ß7, FcRg, Zap70, and CD3z, findings which were more similar to B cells than NK cells. CD20+NKG2a/c+ NKB cells were identified in spleen, mesenteric lymph nodes (MLN), colon, jejunum, and liver of naïve rhesus macaques (RM) via tissue imaging, with NKB cell counts concentrated in spleen and MLN. For the first time, single cell RNA sequencing (scRNAseq), including B cell receptor (BCR) sequencing, of sorted NKB cells confirmed that NKB cells are unique. Transcriptomic analysis of naïve splenic NKB cells by scRNAseq showed that NKB cells undergo somatic hypermutation and express Ig receptors, similar to B cells. While only 15% of sorted NKB cells showed transcript expression of both KLRC1 (NKG2A) and MS4A1 (CD20) genes, only 5% of cells expressed KLRC1, MS4A1, and IgH/IgL transcripts. We observed expanded NKB frequencies in RM gut and buccal mucosa as early as 14 and 35 days post-SIV infection, respectively. Further, mucosal and peripheral NKB cells were associated with colorectal cytokine milieu and oral microbiome changes, respectively. Our studies indicate that NKB cells gated on CD3-CD14-CD20+NKG2A/C+ cells were inclusive of transcriptomically conventional B and NK cells in addition to true NKB cells, confounding accurate phenotyping and frequency recordings that could only be resolved using genomic techniques. Although NKB cells were clearly elevated during SIV infection and associated with inflammatory changes during infection, further interrogation is necessary to acurately identify the true phenotype and significance of NKB cells in infection and inflammation.


Subject(s)
Immunity, Innate , Killer Cells, Natural , Macaca mulatta , Simian Acquired Immunodeficiency Syndrome , Simian Immunodeficiency Virus , Animals , Simian Acquired Immunodeficiency Syndrome/immunology , Simian Acquired Immunodeficiency Syndrome/virology , Simian Immunodeficiency Virus/immunology , Killer Cells, Natural/immunology , B-Lymphocytes/immunology
11.
JAMA Netw Open ; 7(4): e244278, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38587847

ABSTRACT

Importance: Patients with stage IV non-small cell lung cancer (NSCLC) experience substantial morbidity and mortality. Contact days (ie, the number of days with health care contact outside the home) measure how much of a person's life is consumed by health care, yet little is known about patterns of contact days for patients with NSCLC. Objective: To describe the trajectories of contact days in patients with stage IV NSCLC and how trajectories vary by receipt of cancer-directed treatment in routine practice. Design, Setting, and Participants: A retrospective, population-based decedent cohort study was conducted in Ontario, Canada. Participants included adults aged 20 years or older who were diagnosed with stage IV NSCLC (January 1, 2014, to December 31, 2017) and died (January 1, 2014, to December 31, 2019); there was a maximum 2-year follow-up. Data analysis was conducted from February 22 to August 16, 2023. Exposure: Systemic cancer-directed therapy (yes or no) and type of therapy (chemotherapy vs immunotherapy vs targeted therapy). Main Outcomes and Measures: Contact days (days with health care contact, outpatient or institution-based, outside the home) were identified through administrative data. The weekly percentage of contact days and fitted models with cubic splines were quantified to describe trajectories from diagnosis until death. Results: A total of 5785 decedents with stage IV NSCLC were included (median age, 70 [IQR 62-77] years; 3108 [53.7%] were male, and 1985 [34.3%] received systemic therapy). The median overall survival was 108 (IQR, 49-426) days, median contact days were 36 (IQR, 21-62), and the median percentage that were contact days was 33.3%. A median of 5 (IQR, 2-10) days were spent with specialty palliative care. Patients who did not receive systemic therapy had a median overall survival of 66 (IQR, 34-130) days and median contact days of 28 (IQR, 17-44), of which a median of 5 (IQR, 2-9) days were spent with specialty palliative care. Overall and for subgroups, normalized trajectories followed a U-shaped distribution: contact days were most frequent immediately after diagnosis and before death. Patients who received targeted therapy had the lowest contact day rate during the trough (10.6%; vs immunotherapy, 15.4%; vs chemotherapy, 17.7%). Conclusions and Relevance: In this cohort study, decedents with stage IV NSCLC had a median survival in the order of 3.5 months and spent 1 in every 3 days alive interacting with the health care system outside the home. These results highlight the need to better support patients and care partners, benchmark appropriateness, and improve care delivery.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Adult , Humans , Male , Aged , Female , Carcinoma, Non-Small-Cell Lung/therapy , Cohort Studies , Retrospective Studies , Lung Neoplasms/therapy , Outpatients , Delivery of Health Care , Ontario/epidemiology
12.
NPJ Breast Cancer ; 10(1): 24, 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38531875

ABSTRACT

Antibiotic exposure during immunotherapy (IO) has been shown to negatively affect clinical outcomes in various cancer types. The aim of this study was to evaluate whether antibiotic exposure in patients with high-risk early-stage HER2-negative breast cancer (BC) undergoing treatment with neoadjuvant pembrolizumab impacted residual cancer burden (RCB) and pathologic complete response (pCR) in the pembrolizumab-4 arm of the ISPY-2 clinical trial. Patients received pembrolizumab for four cycles concurrently with weekly paclitaxel for 12 weeks, followed by four cycles of doxorubicin plus cyclophosphamide every 2 or 3 weeks. Patients who received at least one dose of systemic antibiotics concurrently at the time of immunotherapy (IO) were included in the antibiotic exposure group (ATB+). All other participants were included in the control group (ATB-). RCB index and PCR rates were compared between the ATB+ and ATB- groups using t-tests and Chi-squared tests, and linear and logistic regression models, respectively. Sixty-six patients were included in the analysis. 18/66 (27%) patients were in the ATB+ group. Antibiotic use during IO was associated with a higher mean RCB index (1.80 ± 1.43 versus 1.08 ± 1.41) and a lower pCR rate (27.8% versus 52.1%). The association between antibiotic use and the RCB index remained significant in multivariable linear regression analysis (RCB index-coefficient 0.86, 95% CI 0.20-1.53, P = 0.01). Our findings suggest that concurrent antibiotic exposure during neoadjuvant pembrolizumab in HER2-negative early-stage BC is associated with higher RCB. Further validation in larger cohorts is needed to confirm these findings.

13.
Cell Rep ; 43(3): 113948, 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38483908

ABSTRACT

Identifying individual functional B cell receptors (BCRs) is common, but two-dimensional analysis of B cell frequency versus BCR potency would delineate both quantity and quality of antigen-specific memory B cells. We efficiently determine quantitative BCR neutralizing activities using a single-cell-derived antibody supernatant analysis (SCAN) workflow and develop a frequency-potency algorithm to estimate B cell frequencies at various neutralizing activity or binding affinity cutoffs. In an HIV-1 fusion peptide (FP) immunization study, frequency-potency curves elucidate the quantity and quality of FP-specific immunoglobulin G (IgG)+ memory B cells for different animals, time points, and antibody lineages at single-cell resolution. The BCR neutralizing activities are mainly determined by their affinities to soluble envelope trimer. Frequency analysis definitively demonstrates dominant neutralizing antibody lineages. These findings establish SCAN and frequency-potency analyses as promising approaches for general B cell analysis and monoclonal antibody (mAb) discovery. They also provide specific rationales for HIV-1 FP-directed vaccine optimization.


Subject(s)
HIV Infections , HIV Seropositivity , HIV-1 , Animals , Antibodies, Neutralizing , HIV Antibodies , Immunoglobulin G , Memory B Cells
14.
Chem Biodivers ; 21(5): e202400075, 2024 May.
Article in English | MEDLINE | ID: mdl-38466656

ABSTRACT

In the present work, we synthesized a small library of 2-phenylindolizine acetamide derivatives 7a-i and studied their biological activity. The synthesis was accomplished starting with easily available starting material phenacyl bromide 1 proceeding through the key intermediate 6-methyl-7-nitro-2-phenylindolizine 4. All the compounds 7a-i were characterized using spectroscopy viz., 1H-NMR, 13C NMR, FTIR, and mass spectrometry. Interestingly, 2-phenylindolizine scaffolds 7c, 7f and 7g revealed a remarkable antibacterial activity against relevant organisms S. aureus, E. coli, S. pneumoniae, P. aeruginosa. The target compounds 7e and 7h showed excellent anticancer activity against Colo-205 and MDA-MB-231 cell lines with IC50 values of 68.62, 62.91, 54.23 and 46.34 µM respectively. Additionally, all the 2-phenylindolizine acetamide derivatives 7a-i were subjected to molecular docking prediction by Autodock 4.2. Compounds 7a, 7f and 7c exhibited very good hydrogen bonding amino acid interactions Asp83 (2.23 Å), Asp83 (2.08 Å), His74 (2.05 Å), His76 (1.71 Å), Ser80 (1.05 Å) with active site of Topoisomerase-IV from S. pneumoniae (4KPE). Further, the compounds 7a-i have revealed acceptable ranges for drug-likeliness properties upon evaluation using SwissADME for ADMET and physiochemical properties.


Subject(s)
Acetamides , Antineoplastic Agents , Drug Design , Drug Screening Assays, Antitumor , Indolizines , Microbial Sensitivity Tests , Molecular Docking Simulation , Humans , Acetamides/chemistry , Acetamides/pharmacology , Acetamides/chemical synthesis , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/chemistry , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Cell Line, Tumor , Cell Proliferation/drug effects , Dose-Response Relationship, Drug , Indolizines/chemistry , Indolizines/pharmacology , Indolizines/chemical synthesis , Molecular Structure , Structure-Activity Relationship , Indoles/chemical synthesis , Indoles/chemistry , Indoles/pharmacology
16.
Int J Artif Organs ; 47(3): 181-189, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38418945

ABSTRACT

BACKGROUND: A subset of patients with COVID-19 acute respiratory distress syndrome (ARDS) require extracorporeal membrane oxygenation (ECMO). Veno-pulmonary (VP) ECMO provides support to the right ventricle and decreased risk of recirculation. METHODS: A retrospective analysis of patients with COVID-19 ARDS and VP ECMO was performed. Patients were separated into groups by indication (1) "right ventricular (RV) failure," (2) "refractory hypoxemia," and (3) "recurrent suck-down events (SDEs)." Pre- and post-configuration vasoactive inotropic scores (VIS), fraction of inspired oxygen (FIO2), and resolution of SDEs were reported. A 90-day mortality was computed for all groups. Patients were also compared to those who underwent conventional venovenous (VV) ECMO. RESULTS: Forty-seven patients underwent VP ECMO configuration, 18 in group 1, 16 in group 2, and 8 in group 3. Ninety-day mortality was 66% for the entire cohort and was 77.8%, 81.3% and 37.5% for groups 1, 2, and 3, respectively. Mean VIS decreased in group 1 (8.3 vs 2.9, p = 0.005), while mean FIO2 decreased in the group 2 and was sustained at 72 h (82.5% vs 52.5% and 47.5%, p < 0.001). Six of the eight (75%) of patients with recurrent SDEs had resolution of these events after configuration to VP ECMO. Patients with VP ECMO spent more days on ECMO (33 days compared to 18 days, p = 0.004) with no difference in mortality (66% compared to 55.1%, p = 0.28). CONCLUSION: VP ECMO in COVID-19 ARDS improves hemodynamics in patients with RV failure, improves oxygenation in patients with refractory hypoxemia and improves the frequency of SDEs.


Subject(s)
COVID-19 , Extracorporeal Membrane Oxygenation , Respiratory Distress Syndrome , Humans , Retrospective Studies , Respiration, Artificial , Hypoxia
17.
Int J Mol Sci ; 25(2)2024 Jan 22.
Article in English | MEDLINE | ID: mdl-38279360

ABSTRACT

The molecular mechanism involved in chickpea (Cicer arietinum L.) resistance to the necrotrophic fungal pathogen Ascochyta rabiei is not well documented. A. rabiei infection can cause severe damage in chickpea, resulting in significant economic losses. Understanding the resistance mechanism against ascochyta blight can help to define strategies to develop resistant cultivars. In this study, differentially expressed genes from two partially resistant cultivars (CDC Corinne and CDC Luna) and a susceptible cultivar (ICCV 96029) to ascochyta blight were identified in the early stages (24, 48 and 72 h) of A. rabiei infection using RNA-seq. Altogether, 3073 genes were differentially expressed in response to A. rabiei infection across different time points and cultivars. A larger number of differentially expressed genes (DEGs) were found in CDC Corinne and CDC Luna than in ICCV 96029. Various transcription factors including ERF, WRKY, bHLH and MYB were differentially expressed in response to A. rabiei infection. Genes involved in pathogen detection and immune signalings such as receptor-like kinases (RLKs), Leucine-Rich Repeat (LRR)-RLKs, and genes associated with the post-infection defence response were differentially expressed among the cultivars. GO functional enrichment and pathway analysis of the DEGs suggested that the biological processes such as metabolic process, response to stimulus and catalytic activity were overrepresented in both resistant and susceptible chickpea cultivars. The expression patterns of eight randomly selected genes revealed by RNA-seq were confirmed by quantitative PCR (qPCR) analysis. The results provide insights into the complex molecular mechanism of the chickpea defence in response to the A. rabiei infection.


Subject(s)
Ascomycota , Cicer , Cicer/genetics , Plant Diseases/genetics , Plant Diseases/microbiology , Ascomycota/physiology
18.
Int J Mol Sci ; 25(1)2024 Jan 04.
Article in English | MEDLINE | ID: mdl-38203819

ABSTRACT

The availability of wild chickpea (Cicer reticulatum L.) accessions has the potential to be used for the improvement of important traits in cultivated chickpeas. The main objectives of this study were to evaluate the phenotypic and genetic variations of chickpea progeny derived from interspecific crosses between C. arietinum and C. reticulatum, and to establish the association between single nucleotide polymorphism (SNP) markers and a series of important agronomic traits in chickpea. A total of 486 lines derived from interspecific crosses between C. arietinum (CDC Leader) and 20 accessions of C. reticulatum were evaluated at different locations in Saskatchewan, Canada in 2017 and 2018. Significant variations were observed for seed weight per plant, number of seeds per plant, thousand seed weight, and plant biomass. Path coefficient analysis showed significant positive direct effects of the number of seeds per plant, thousand seed weight, and biomass on the total seed weight. Cluster analysis based on the agronomic traits generated six groups that allowed the identification of potential heterotic groups within the interspecific lines for yield improvement and resistance to ascochyta blight disease. Genotyping of the 381 interspecific lines using a modified genotyping by sequencing (tGBS) generated a total of 14,591 SNPs. Neighbour-joining cluster analysis using the SNP data grouped the lines into 20 clusters. The genome wide association analysis identified 51 SNPs that had significant associations with different traits. Several candidate genes associated with early flowering and yield components were identified. The candidate genes and the significant SNP markers associated with different traits have a potential to aid the trait introgression in the breeding program.


Subject(s)
Cicer , Cicer/genetics , Genome-Wide Association Study , Alleles , Plant Breeding , Seeds
19.
ASAIO J ; 70(5): 427-435, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38295398

ABSTRACT

Emerging evidence suggests prolonged use of noninvasive respiratory support may increase mortality of patients with coronavirus disease 2019 (COVID-19)-associated acute respiratory distress syndrome who require extracorporeal membrane oxygenation (ECMO). Using a database of adults receiving ECMO for COVID-19, we calculated survival curves and multivariable Cox regression to determine the risk of death associated with pre-ECMO use of high-flow nasal oxygen (HFNO), noninvasive ventilation (NIV), and invasive mechanical ventilation (IMV) days. We investigated the performance of a novel variable, advanced respiratory support days (composite of HFNO, NIV, and IMV days), on Respiratory ECMO Survival Prediction (RESP) score. Subjects (N = 146) with increasing advanced respiratory support days (<5, 5-9, and ≥10) had a stepwise increase in 90 day mortality (32.2%, 57.7%, and 75.4%, respectively; p = 0.002). Ninety-day mortality was significantly higher in subjects (N = 121) receiving NIV >4 days (81.8% vs. 52.4%, p < 0.001). Each additional pre-ECMO advanced respiratory support day increased the odds of right ventricular failure (odds ratio [OR]: 1.066, 95% confidence interval [CI]: 1.002-1.135) and in-hospital mortality (1.17, 95% CI: 1.08-1.27). Substituting advanced respiratory support days for IMV days improved RESP score mortality prediction (area under the curve (AUC) or: 0.64 vs. 0.71). Pre-ECMO advanced respiratory support days were associated with increased 90 day mortality compared with IMV days alone. Adjusting the RESP score for advanced respiratory support days improved mortality prediction.


Subject(s)
COVID-19 , Extracorporeal Membrane Oxygenation , Respiratory Distress Syndrome , Humans , Extracorporeal Membrane Oxygenation/methods , COVID-19/mortality , COVID-19/therapy , COVID-19/complications , Male , Female , Middle Aged , Respiratory Distress Syndrome/therapy , Respiratory Distress Syndrome/mortality , Aged , Adult , Retrospective Studies , Respiration, Artificial , Noninvasive Ventilation/methods , SARS-CoV-2 , Hospital Mortality
20.
J Pediatr Pharmacol Ther ; 28(6): 524-529, 2023.
Article in English | MEDLINE | ID: mdl-38130341

ABSTRACT

OBJECTIVE: Pruritus is a common symptom of liver disease, managed with various medications including opioid antagonists like naltrexone. Current literature surrounding the safety and efficacy of naltrexone for cholestatic pruritus is limited. Our objective was to describe naltrexone prescribing practices for cholestatic pruritus. METHODS: We conducted a single-center, retrospective review of inpatients who received naltrexone for cholestatic pruritus. We gathered information on naltrexone dosing, frequency, dose adjustments, duration, elevations in liver function tests (LFTs), and use of additional antipruritic agents. RESULTS: Thirty-nine patients and 122 dosing regimens were included for analysis. Most patients were male (56.4%) with a median age of 6.32 years (range, 0.63-18.89). The median weight-based doses of naltrexone were 1.45 mg/kg/dose (IQR, 0.84-2.81) and 1.86 mg/kg/day (IQR, 0.97-3.37). The median flat doses were 25 mg/dose (IQR, 12.25-50) and 50 mg/day (IQR, 25-50). The median number of additional antipruritic agents used before and after naltrexone initiation was 3 (IQR, 2-4) and 4 (IQR, 3-5), respectively (p < 0.001). The most common elevated LFTs were total bilirubin and alanine aminotransferase (ALT), occurring in 15% of patients. CONCLUSIONS: Naltrexone dosing ranged between 1 and 2 mg/kg/dose once or twice daily, with larger weight-based doses prescribed in younger and lower-weight patients. Naltrexone was commonly added as a fourth-line agent and did not lead to discontinuation of other antipruritic therapies. Larger, prospective, controlled studies are needed to assess the safety and efficacy of naltrexone for cholestatic pruritus.

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