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1.
RSC Adv ; 14(15): 10590-10607, 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38567346

ABSTRACT

This paper presents a simple and cost-effective hydrogenation method for synthesizing a myriad of cycloalkanes and saturated heterocycles bearing boryl or silyl substituents. The catalyst used are heterogeneous, readily available, bench stable, and recyclable. Also demonstrated is the application of the method to compounds that possess both boryl and silyl groups. When combined with Ir-catalyzed sp2 C-H borylation, such hydrogenations offer a two-step complementary alternative to direct sp3 C-H borylations that can suffer selectivity and reactivity issues. Of practical value to the community, complete stereochemical analyses of reported borylated compounds that were never fully characterized are reported herein.

2.
J Org Chem ; 89(9): 6048-6052, 2024 May 03.
Article in English | MEDLINE | ID: mdl-38640193

ABSTRACT

Tetraalkoxydiborons can be easily prepared by acid-catalyzed reactions of tetrahydroxydiboron or its anhydride with trialkyl orthoformates. Addition of diols to these reaction mixtures afforded diboron diolates in high yield. In both cases, removal of volatile byproducts is all that is required for the isolation of the diboron. These methods constitute a convenient alternative to previous preparations from tetrakis (dimethylamino) diboron and tetrahydroxydiboron.

3.
Nat Commun ; 15(1): 2302, 2024 Mar 14.
Article in English | MEDLINE | ID: mdl-38485761

ABSTRACT

A mobile colistin resistance gene mcr was first reported in 2016 in China and has since been found with increasing prevalence across South-East Asia. Here we survey the presence of mcr genes in 4907 rectal swabs from mothers and neonates from three hospital sites across Nigeria; a country with limited availability or history of colistin use clinically. Forty mother and seven neonatal swabs carried mcr genes in a range of bacterial species: 46 Enterobacter spp. and single isolates of; Shigella, E. coli and Klebsiella quasipneumoniae. Ninety percent of the genes were mcr-10 (n = 45) we also found mcr-1 (n = 3) and mcr-9 (n = 1). While the prevalence during this collection (2015-2016) was low, the widespread diversity of mcr-gene type and range of bacterial species in this sentinel population sampling is concerning. It suggests that agricultural colistin use was likely encouraging sustainment of mcr-positive isolates in the community and implementation of medical colistin use will rapidly select and expand resistant isolates.


Subject(s)
Colistin , Escherichia coli Proteins , Pregnancy , Infant, Newborn , Female , Humans , Colistin/pharmacology , Escherichia coli/genetics , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Pregnant Women , Nigeria/epidemiology , Drug Resistance, Bacterial/genetics , Escherichia coli Proteins/genetics , Microbial Sensitivity Tests , Plasmids
4.
J Am Chem Soc ; 145(48): 26339-26349, 2023 Dec 06.
Article in English | MEDLINE | ID: mdl-38011890

ABSTRACT

We report an in-depth investigation into the ammonia oxidation mechanism by the catalyst [RuIII(tpy)(dmabpy)NH3]3+ ([Ru(NH3)]3+). Stoichiometric reactions of [Ru(NH3)]3+ were carried out with exogenous noncoordinating bases to trigger a proposed redox disproportionation reaction, which was followed using variable-temperature NMR spectroscopy. An intermediate species was identified as a dinitrogen-bridged complex using 15N NMR and Raman spectroscopy on isotopically labeled complexes. This intermediate is proposed to derive from coupling of nitridyl species formed upon sequential redox disproportion reactions. Acetonitrile displaces the dinitrogen bridge to yield free N2. DFT calculations support this lower-energy pathway versus that previously reported for ammonia oxidation by the parent [RuIII(tpy)(bpy)NH3]3+ complex. These experimental and computational results are consistent with the interpretation of redox disproportionation involving sequential hydrogen atom transfer reactions by an amide/aminyl intermediate, [Ru(NH2)-]+ ⇔ [Ru(NH2)•]+, formed upon deprotonation of the parent complex. Control experiments employing a large excess of ammonia as a base indicate this new proposed lower-energy pathway contributes to the oxidation of ammonia to dinitrogen in conditions relevant to electrocatalysis. In addition, analogous methylamine complexes, [Ru(NH2CH3)]2+/3+, were prepared to further test the proposed mechanism. Treating [Ru(NH2CH3)]3+ with a base cleanly yields two products [Ru(NH2CH3)]2+ and [Ru(CN)]+ in an ∼3:1 ratio, fully consistent with the proposed cascade of hydrogen atom transfer reactions by an intermediate.

5.
Can Vet J ; 64(11): 1051-1057, 2023 11.
Article in English | MEDLINE | ID: mdl-37915779

ABSTRACT

Objective: Corticosteroids are indicated to treat many feline diseases. However, side effects are a limiting factor in their use. The most concerning side effects are steroid-induced diabetes mellitus (SI-DM) and steroid-induced congestive heart failure (SI-CHF). This study aims to determine the incidences of these diseases in a large population of domestic cats seen at a privately-owned, feline-only practice. Animals: Cats in the study were client-owned patients of Alamo Feline Health Center in San Antonio, Texas. Control cats (controls) were examined as part of their routine health care. Procedures: The records of 732 cats that received methylprednisolone acetate (MPA) for various clinical indications were reviewed to determine how many developed SI-DM and SI-CHF. A similar record review of 310 controls was made to determine the incidence of spontaneous diabetes mellitus (Sp-DM) and spontaneous congestive heart failure (Sp-CHF). Control cats never received any oral or injectable corticosteroids. Results: Of the cats that received MPA, 28 developed SI-DM (3.83%) and 6 developed SI-CHF (0.82%). Of the controls, 22 developed Sp-DM (7.10%) and 6 developed Sp-CHF (1.90%). Conclusion: The incidences of developing SI-DM and SI-CHF were 3.83% and 0.82%, respectively; and the risk was not increased even when repeated doses of MPA were given. Clinical relevance: The authors consider the risk-benefit ratio sufficient to justify the use of MPA when it is indicated, especially if another drug cannot be substituted with the same therapeutic results.


Incidences du diabète sucré et de l'insuffisance cardiaque congestive induits par les stéroïdes chez des chats ayant reçu des doses non immunosuppressives d'acétate de méthylprednisolone : 1042 chats. Objectif: Les corticoïdes sont indiqués pour traiter de nombreuses maladies félines. Cependant, les effets secondaires constituent un facteur limitant leur utilisation. Les effets secondaires les plus préoccupants sont le diabète sucré induit par les stéroïdes (SI-DM) et l'insuffisance cardiaque congestive induite par les stéroïdes (SI-CHF). Cette étude vise à déterminer l'incidence de ces maladies dans une large population de chats domestiques vus dans une pratique privée exclusivement féline. Animaux: Les chats de l'étude étaient des patients appartenant à des clients du Alamo Feline Health Center à San Antonio, au Texas. Les chats témoins (témoins) ont été examinés dans le cadre de leurs soins de santé de routine. Procédures: Les dossiers de 732 chats ayant reçu de l'acétate de méthylprednisolone (MPA) pour diverses indications cliniques ont été examinés afin de déterminer combien d'entre eux ont développé du SI-DM et du SI-CHF. Un examen similaire des dossiers de 310 témoins a été réalisé pour déterminer l'incidence du diabète sucré spontané (Sp-DM) et de l'insuffisance cardiaque congestive spontanée (Sp-CHF). Les chats témoins n'ont jamais reçu de corticostéroïdes oraux ou injectables. Résultats: Parmi les chats ayant reçu du MPA, 28 ont développé du SI-DM (3,83 %) et 6 ont développé du SI-CHF (0,82 %). Parmi les témoins, 22 ont développé du Sp-DM (7,10 %) et 6 ont développé du Sp-CHF (1,90 %). Conclusion: Les incidences de développement de SI-DM et de SI-CHF étaient respectivement de 3,83 % et 0,82 %; et le risque n'a pas augmenté même lorsque des doses répétées de MPA ont été administrées. Pertinence clinique: Les auteurs considèrent le rapport bénéfice/risque suffisant pour justifier l'utilisation du MPA lorsqu'il est indiqué, notamment si un autre médicament ne peut lui être substitué avec les mêmes résultats thérapeutiques.(Traduit par Dr Serge Messier).


Subject(s)
Cat Diseases , Diabetes Mellitus , Heart Failure , Cats , Animals , Methylprednisolone Acetate , Incidence , Heart Failure/chemically induced , Heart Failure/epidemiology , Heart Failure/veterinary , Diabetes Mellitus/veterinary , Adrenal Cortex Hormones , Cat Diseases/chemically induced , Cat Diseases/epidemiology
6.
Org Lett ; 25(45): 8057-8061, 2023 Nov 17.
Article in English | MEDLINE | ID: mdl-37939287

ABSTRACT

Traditional reaction conditions in Ir-catalyzed C-H borylation consist of a 2:1 ligand to Ir metal ratio, affording C(sp2)-H borylation at the least sterically hindered position. We found that lowering the ligand to metal ratio of a N,B-type diboron (BB) preligand in respect to the IrI precatalyst to 0.5:1 affords the chelate controlled ortho product. Switching from steric-directed to chelate-directed products is shown for various substituted arenes and (hetero)arenes containing Lewis-basic functionalities. This work offers the first example of obtaining complementary regioisomers as the major product by altering the ligand loading in CHB.

7.
Commun Med (Lond) ; 3(1): 108, 2023 Aug 09.
Article in English | MEDLINE | ID: mdl-37558833

ABSTRACT

BACKGROUND: Genetically engineered mouse models (GEMMs) of cancer are powerful tools to study mechanisms of disease progression and therapy response, yet little is known about how these models respond to multimodality therapy used in patients. Radiation therapy (RT) is frequently used to treat localized cancers with curative intent, delay progression of oligometastases, and palliate symptoms of metastatic disease. METHODS: Here we report the development, testing, and validation of a platform to immobilize and target tumors in mice with stereotactic ablative RT (SART). Xenograft and autochthonous tumor models were treated with hypofractionated ablative doses of radiotherapy. RESULTS: We demonstrate that hypofractionated regimens used in clinical practice can be effectively delivered in mouse models. SART alters tumor stroma and the immune environment, improves survival in GEMMs of primary prostate and colorectal cancer, and synergizes with androgen deprivation in prostate cancer. Complete pathologic responses were achieved in xenograft models, but not in GEMMs. CONCLUSIONS: While SART is capable of fully ablating xenografts, it is unable to completely eradicate disease in GEMMs, arguing that resistance to potentially curative therapy can be modeled in GEMMs.


Mice can be used to model the types of cancer seen in people to investigate the effects of cancer therapies, such as radiation. Here, we apply radiation therapy treatments that are able to cure cancer in humans to mice that have cancer of the prostate or colorectum. We show that the mice do not experience many side effects and that the tumours reduce in size, but in some cases show progression after treatment. Our study demonstrates that mice can be used to better understand how human cancers respond to radiation treatment, which can lead to the development of improved treatments and treatment schedules.

8.
Ann R Coll Surg Engl ; 105(6): 540-547, 2023 Jul.
Article in English | MEDLINE | ID: mdl-36779446

ABSTRACT

INTRODUCTION: The long-term outcomes of chest trauma are largely unknown. We sought to determine the predictors of in-hospital and long-term survival in patients admitted to a major trauma centre (MTC) with chest injuries and to evaluate spatial patterns of injury in our network area. METHODS: Retrospective analysis of data collected on the National Trauma Audit Research Network (TARN) database using multivariate analysis and Cox regression analysis. Spatial analysis was performed using ArcGis 10.7.1. RESULTS: Some 5,680 patients were admitted with chest trauma between December 1999 and December 2019. Median patient age was 45 years and the median Injury Severity Score (ISS) was 20. The proportion of patients who had an operation was 39.8%. Age, blood transfusion, head injury, shock, emergency thoracotomy and heart disease were predictors of hospital mortality (p < 0.05). However, having an operation on concomitant injuries was protective. ISS and Glasgow Coma Score were discriminators of in-hospital mortality (C-indices 0.76 and 0.80, respectively). The 10-year survival values for patients who survived to discharge from hospital and who were aged <40, 50, 60, 70, 80 and >80 years were 99%, 93%, 95%, 87%, 75% and 43%, respectively. Preadmission lung disease and alcohol/drug misuse were poor predictors of long-term survival (p < 0.05). Hotspot analysis revealed the areas with the highest incidents were all close to the MTC. CONCLUSIONS: The MTC is geographically central to areas with high numbers of trauma incidents. Although emergency thoracotomy was a predictor of poor in-hospital outcomes, having surgery for concomitant injuries improved outcomes. Patients surviving to discharge have good long-term survivals.


Subject(s)
Thoracic Injuries , Trauma Centers , Humans , Retrospective Studies , Thoracic Injuries/epidemiology , Thoracic Injuries/surgery , Hospitalization , Injury Severity Score , United Kingdom/epidemiology
9.
Anaesthesia ; 78(2): 225-235, 2023 02.
Article in English | MEDLINE | ID: mdl-36572548

ABSTRACT

Managing major thoracic trauma begins with identifying and anticipating injuries associated with the mechanism of injury. The key aims are to reduce early mortality and the impact of associated complications to expedite recovery and restore the patient to their pre-injury state. While imaging is imperative to identify the extent of thoracic trauma, some pathology may require immediate treatment. The majority can be managed with adequate pleural drainage, but respiratory failure and poor gas exchange may require either non-invasive or invasive ventilation. Ventilation strategies to protect from complications such as barotrauma, volutrauma and ventilator-induced lung injury are important to consider. The management of pain is vital in reducing respiratory complications. A multimodal strategy using local, regional and systemic analgesia may mitigate respiratory side effects of opioid use. With optimal pain management, physiotherapy can be fully utilised to reduce respiratory complications and enhance early recovery. Thoracic surgeons should be consulted early for consideration of surgical management of specific injuries. With a greater understanding of the mechanisms of injury and the appropriate use of available resources, favourable outcomes can be reached in this cohort of patients. Overall, a multidisciplinary and holistic approach results in the best patient outcomes.


Subject(s)
Analgesia , Thoracic Injuries , Humans , Thoracic Injuries/therapy , Thoracic Injuries/complications , Pain/etiology , Pain Management/methods , Analgesia/methods , Lung
10.
Int J Med Mushrooms ; 24(11): 83-95, 2022.
Article in English | MEDLINE | ID: mdl-36374951

ABSTRACT

Cancer is the second leading cause of death worldwide, and despite of the of the availability of the advanced chemical treatments, development of effective and safe alternatives derived from natural resources are still of high interest. Mushroom is one of the important resources of pharmacologically active cytotoxic compounds. In this paper, we report the cytotoxicity of ethanolic extracts of Oudemansiella canarii (Jungh.) Höhn. and Ganoderma lucidum (W. Curt.: Fr.) P. Karst. against nine hematologic malignant cells and describe their molecular mechanisms. Cell lines were exposed to varying concentrations of mushroom extracts for 48 h and the cell proliferation and apoptosis parameters were determined. Western blot analysis was performed to determine the extract-induced changes in the level of apoptosis-related proteins in cancer cell lines and patient-derived mononuclear cells. Results revealed that O. canarii and G. lucidum extracts exhibited cytotoxicity with IC50 values of 26.8-66.0 ppm and 48.1-78.4 ppm, respectively, in all the cancer cell lines used. Mushroom extracts inhibited cell proliferation by 57.3-72.5% (O. canarii) and 44.2-67.4% (G. lucidum), which correlates to the activation of apoptosis as indicated by increased annexin V positivity, cells in sub G0/G1 phase and production of reactive oxygen species, and decreased mitochondrial membrane potential. Western blot analysis showed increase in the level of apoptotic markers (cleaved PARP1, cleaved caspase 3 and phosphorylation of histone 2AX) and activation of the stress-activated protein kinase (SAPK/JNK) signaling pathway. The extract-activated apoptosis was also observed in mononuclear cells isolated from the peripheral blood of leukemia and lymphoma patients. In conclusion, activation of pro-apoptotic markers is one of the major mechanisms of the cytotoxicity of O. canarii and G. lucidum extracts against hematologic malignant cells.


Subject(s)
Agaricales , Hematologic Neoplasms , Phytotherapy , Plant Extracts , Reishi , Humans , Apoptosis/drug effects , Cell Line, Tumor/drug effects , Cell Proliferation/drug effects , Hematologic Neoplasms/drug therapy , Plant Extracts/pharmacology
11.
Nat Microbiol ; 7(9): 1337-1347, 2022 09.
Article in English | MEDLINE | ID: mdl-35927336

ABSTRACT

Early development of the microbiome has been shown to affect general health and physical development of the infant and, although some studies have been undertaken in high-income countries, there are few studies from low- and middle-income countries. As part of the BARNARDS study, we examined the rectal microbiota of 2,931 neonates (term used up to 60 d) with clinical signs of sepsis and of 15,217 mothers screening for blaCTX-M-15, blaNDM, blaKPC and blaOXA-48-like genes, which were detected in 56.1%, 18.5%, 0% and 4.1% of neonates' rectal swabs and 47.1%, 4.6%, 0% and 1.6% of mothers' rectal swabs, respectively. Carbapenemase-positive bacteria were identified by MALDI-TOF MS and showed a high diversity of bacterial species (57 distinct species/genera) which exhibited resistance to most of the antibiotics tested. Escherichia coli, Klebsiella pneumoniae and Enterobacter cloacae/E. cloacae complex, the most commonly found isolates, were subjected to whole-genome sequencing analysis and revealed close relationships between isolates from different samples, suggesting transmission of bacteria between neonates, and between neonates and mothers. Associations between the carriage of antimicrobial resistance genes (ARGs) and healthcare/environmental factors were identified, and the presence of ARGs was a predictor of neonatal sepsis and adverse birth outcomes.


Subject(s)
Gastrointestinal Microbiome , Sepsis , Anti-Bacterial Agents , Developing Countries , Drug Resistance, Microbial , Escherichia coli , Female , Humans , Infant , Infant, Newborn , Microbial Sensitivity Tests , Mothers
12.
Eur J Obstet Gynecol Reprod Biol ; 276: 161-167, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35914420

ABSTRACT

OBJECTIVE: To assess perinatal outcomes for pregnancies affected by suspected or confirmed SARS-CoV-2 infection. METHODS: Prospective, web-based registry. Pregnant women were invited to participate if they had suspected or confirmed SARS-CoV-2 infection between 1st January 2020 and 31st March 2021 to assess the impact of infection on maternal and perinatal outcomes including miscarriage, stillbirth, fetal growth restriction, pre-term birth and transmission to the infant. RESULTS: Between April 2020 and March 2021, the study recruited 8239 participants who had suspected or confirmed SARs-CoV-2 infection episodes in pregnancy between January 2020 and March 2021. Maternal death affected 14/8197 (0.2%) participants, 176/8187 (2.2%) of participants required ventilatory support. Pre-eclampsia affected 389/8189 (4.8%) participants, eclampsia was reported in 40/ 8024 (0.5%) of all participants. Stillbirth affected 35/8187 (0.4 %) participants. In participants delivering within 2 weeks of delivery 21/2686 (0.8 %) were affected by stillbirth compared with 8/4596 (0.2 %) delivering ≥ 2 weeks after infection (95 % CI 0.3-1.0). SGA affected 744/7696 (9.3 %) of livebirths, FGR affected 360/8175 (4.4 %) of all pregnancies. Pre-term birth occurred in 922/8066 (11.5%), the majority of these were indicated pre-term births, 220/7987 (2.8%) participants experienced spontaneous pre-term births. Early neonatal deaths affected 11/8050 livebirths. Of all neonates, 80/7993 (1.0%) tested positive for SARS-CoV-2. CONCLUSIONS: Infection was associated with indicated pre-term birth, most commonly for fetal compromise. The overall proportions of women affected by SGA and FGR were not higher than expected, however there was the proportion affected by stillbirth in participants delivering within 2 weeks of infection was significantly higher than those delivering ≥ 2 weeks after infection. We suggest that clinicians' threshold for delivery should be low if there are concerns with fetal movements or fetal heart rate monitoring in the time around infection. The proportion affected by pre-eclampsia amongst participants was not higher than would be expected, although we report a higher than expected proportion affected by eclampsia. There appears to be no effect on birthweight or congenital malformations in women affected by SARS-CoV-2 infection in pregnancy and neonatal infection is uncommon. This study reflects a population with a range of infection severity for SARS-COV-2 in pregnancy, generalisable to whole obstetric populations.


Subject(s)
COVID-19 , Eclampsia , Pre-Eclampsia , Pregnancy Complications, Infectious , Premature Birth , COVID-19/complications , COVID-19/epidemiology , Female , Humans , Infant , Infant, Newborn , Pre-Eclampsia/epidemiology , Pregnancy , Pregnancy Complications, Infectious/epidemiology , Pregnancy Outcome/epidemiology , Premature Birth/epidemiology , Prospective Studies , SARS-CoV-2 , Stillbirth/epidemiology
13.
J Cyst Fibros ; 21(6): 967-976, 2022 11.
Article in English | MEDLINE | ID: mdl-35732550

ABSTRACT

BACKGROUND: Macrophages are the major resident immune cells in human airways coordinating responses to infection and injury. In cystic fibrosis (CF), neutrophils are recruited to the airways shortly after birth, and actively exocytose damaging enzymes prior to chronic infection, suggesting a potential defect in macrophage immunomodulatory function. Signaling through the exhaustion marker programmed death protein 1 (PD-1) controls macrophage function in cancer, sepsis, and airway infection. Therefore, we sought to identify potential associations between macrophage PD-1 and markers of airway disease in children with CF. METHODS: Blood and bronchoalveolar lavage fluid (BALF) were collected from 45 children with CF aged 3 to 62 months and structural lung damage was quantified by computed tomography. The phenotype of airway leukocytes was assessed by flow cytometry, while the release of enzymes and immunomodulatory mediators by molecular assays. RESULTS: Airway macrophage PD-1 expression correlated positively with structural lung damage, neutrophilic inflammation, and infection. Interestingly, even in the absence of detectable infection, macrophage PD-1 expression was elevated and correlated with neutrophilic inflammation. In an in vitro model mimicking leukocyte recruitment into CF airways, soluble mediators derived from recruited neutrophils directly induced PD-1 expression on recruited monocytes/macrophages, suggesting a causal link between neutrophilic inflammation and macrophage PD-1 expression in CF. Finally, blockade of PD-1 in a short-term culture of CF BALF leukocytes resulted in improved pathogen clearance. CONCLUSION: Taken together, these findings suggest that in early CF lung disease, PD-1 upregulation associates with airway macrophage exhaustion, neutrophil takeover, infection, and structural damage.


Subject(s)
Cystic Fibrosis , Child , Humans , Programmed Cell Death 1 Receptor , Lung , Inflammation , Bacteria/metabolism , Biomarkers/metabolism , Macrophages
14.
Pediatr Pulmonol ; 57(9): 2189-2198, 2022 09.
Article in English | MEDLINE | ID: mdl-35637404

ABSTRACT

BACKGROUND: In this pilot study, we investigated whether induced sputum (IS) could serve as a viable alternative to bronchoalveolar lavage (BAL) and yield robust inflammatory biomarkers in toddlers with cystic fibrosis (CF) featuring minimal structural lung disease. METHODS: We collected IS, BAL (right middle lobe and lingula), and blood, and performed chest computed tomography (CT) scans from 2-year-olds with CF (N = 11), all within a single visit. Inflammatory biomarkers included 20 soluble immune mediators and neutrophil elastase (NE), as well as frequency and phenotype of T cells, monocytes/macrophages, and neutrophils. RESULTS: At the molecular level, nine mediators showed similar levels in IS and BAL (CXCL1, CXCL8, IL-1α, IL-1RA, IL-6, CCL2, CXCL10, M-CSF, VEGF-A), four were higher in IS than in BAL (CXCL5, IL-1ß, CXCL11, TNFSF10), and two were present in IS, but undetectable in BAL (IL-10, IFN-γ). Meanwhile, soluble NE had lower activity in IS than in BAL. At the cellular level, T-cell frequency was lower in IS than in BAL. Monocytes/macrophages were dominant in IS and BAL with similar frequencies, but differing expression of CD16 (lower in IS), CD115, and surface-associated NE (higher in IS). Neutrophil frequency and phenotype did not differ between IS and BAL. Finally, neutrophil frequency in IS correlated positively with air trapping. CONCLUSIONS: IS collected from 2-year-olds with CF yields biomarkers of early airway inflammation with good agreement with BAL, notably with regard to molecular and cellular outcomes related to neutrophils and monocytes/macrophages.


Subject(s)
Cystic Fibrosis , Sputum , Biomarkers , Bronchoalveolar Lavage , Bronchoalveolar Lavage Fluid , Humans , Neutrophils , Pilot Projects
15.
J Glob Antimicrob Resist ; 29: 113-115, 2022 06.
Article in English | MEDLINE | ID: mdl-35189373

ABSTRACT

OBJECTIVES: Extended-spectrum ß-lactamase (ESBL)-producing Enterobacter cloacae complex (ECC) members have been a leading cause of severe infections in hospital setting and have lately been recognized as important pathogens for animals. In this article, we report phylogenomic data of a multidrug-resistant and CTX-M-15-positive E. hormaechei belonging to ST78 isolated from a calf with omphalitis. METHODS: Genomic DNA was extracted and sequenced using the Illumina NextSeq platform. De novo assembly was performed by Unicycler and in silico prediction accomplished by curated bioinformatics tools. Single nucleotide polymorphism (SNP)-based comparative phylogenomic analysis was conducted by using publicly available ECC genomes belonging to ST78. RESULTS: The genome size was calculated at 3 8465 40 bp, comprising 4717 total genes, 3 rRNAs, 43 tRNAs, 7 ncRNAs, and 74 pseudogenes. The animal-associated E. hormaechei (ECBEZ strain) ST78 harboured the blaCTX-M-15 ESBL gene in addition to other critically important resistance genes conferring resistance to ß-lactams, aminoglycosides, fosfomycin, phenicol, quinolones, sulphonamides, tetracyclines, and trimethoprim. Phylogenetic analysis revealed that ECBEZ is closely related to human-isolated strains from Asian and African countries. CONCLUSION: Phylogenomic analysis of CTX-M-15-producing E. hormaechei from animal infection reveals that ST78 is a successful One Health clone among ECC members. Furthermore, data presented in this study reinforce the urgent need to monitor ESBL-producing ECC members in veterinary settings.


Subject(s)
Enterobacter , beta-Lactamases , Animals , Anti-Bacterial Agents/pharmacology , Cattle , Clone Cells , Enterobacter/genetics , Enterobacter/isolation & purification , Enterobacter cloacae/genetics , Enterobacteriaceae Infections/microbiology , Enterobacteriaceae Infections/veterinary , Genome, Bacterial , One Health , Phylogeny , beta-Lactamases/genetics
16.
J Leukoc Biol ; 112(4): 707-716, 2022 10.
Article in English | MEDLINE | ID: mdl-35172381

ABSTRACT

Cystic fibrosis (CF) airways feature high extracellular levels of the IL-1 family of proinflammatory mediators. These mediators are cleavage products of caspase-1, the final protease in the inflammasome cascade. Due to the proven chronic presence of reprogrammed neutrophils in the CF airway lumen, understanding inflammasome signaling in these cells is of great importance to understand how disease is perpetuated in this milieu. Here, we hypothesized that CF airway neutrophils contribute to chronic inflammation, in part, via the packaging of inflammasome-inducing signals in extracellular vesicles (EVs). We confirmed that CF airway fluid is enriched in IL-1α, IL-1ß, and IL-18, and that CF airway neutrophils up-regulate the activating receptor IL-1R1. Meanwhile, down-modulatory signals such as IL-1R2 and IL-1RA are unchanged. Active caspase-1 itself is present in CF airway fluid EVs, with neutrophil-derived EVs being most enriched. Using a transmigration model of CF airway inflammation, we show that CF airway fluid EVs are necessary and sufficient to induce primary granule exocytosis by naïve neutrophils (hallmark of reprogramming) and concomitantly activate caspase-1 and IL-1ß production by these cells and that the addition of triple-combination highly effective CFTR modulator therapy does not abrogate these effects. Finally, EVs from activated neutrophils can deliver active caspase-1 to primary tracheal epithelial cells and induce their release of IL-1α. These findings support the existence of a feed-forward inflammatory process by which reprogrammed CF airway neutrophils bypass 2-step control of inflammasome activation in neighboring cells (naïve neutrophils and epithelial cells) via the transfer of bioactive EVs.


Subject(s)
Cystic Fibrosis , Extracellular Vesicles , Caspases , Cystic Fibrosis Transmembrane Conductance Regulator , Humans , Inflammasomes , Inflammation , Interleukin 1 Receptor Antagonist Protein , Interleukin-18 , Neutrophils , Peptide Hydrolases , Receptors, Interleukin-1 Type II
17.
J Org Chem ; 87(1): 751-759, 2022 01 07.
Article in English | MEDLINE | ID: mdl-34889604

ABSTRACT

A versatile and efficient method to prepare borylated arenes furnished with alkyl, alkenyl, alkynyl, aryl, and heteroaryl functional groups is developed by merging Ir-catalyzed C-H borylations (CHB) with a chemoselective palladium-catalyzed cross-coupling of triorganoindium reagents (Sarandeses-Sestelo coupling) with aryl halides bearing a boronic ester substituent. Using triorganoindium cross-coupling reactions to introduce unsaturated moieties enables the synthesis of borylated arenes that would be difficult to access through the direct application of the CHB methodology. The sequential double catalyzed procedure can be also performed in one vessel.


Subject(s)
Iridium , Palladium , Boron , Catalysis , Indicators and Reagents
18.
Tetrahedron ; 1092022 Mar 12.
Article in English | MEDLINE | ID: mdl-36684041

ABSTRACT

A bidentate monoanionic ligand system was developed to enable iridium catalyzed C(sp3)-H activation borylation of N-methyl amides. Borylated amides were obtained in moderate to good isolated yields, and exclusive mono-borylation allowed the amide to be the limiting reagent. Selectivity for C(sp3)-H activation was demonstrated in the presence of sterically available C(sp3)-H bonds. Competitive kinetic isotope studies revealed a large primary isotope effect, implicating C-H activation as the rate limiting step.

19.
ACS Catal ; 12(4): 2694-2705, 2022 Feb 18.
Article in English | MEDLINE | ID: mdl-36685107

ABSTRACT

Regioselectivities in catalytic C-H borylations (CHBs) have been rationalized using simplistic steric models and correlations with nuclear magnetic resonance (NMR) chemical shifts. However, regioselectivity can be significant for important substrate classes where none would be expected from these arguments. In this study, intramolecular hydrogen bonding (IMHB) can lead to steric shielding effects that can direct Ir-catalyzed CHB regiochemistry. Bpin (Bpin = pinacol boronic ester)/arene IMHB can promote remote borylations of N-borylated anilines, 2-amino-N-alkylpyridine, tetrahydroquinolines, indoles, and 1-borylated naphthalenes. Experimental and computational studies support molecular geometries with the Bpin orientation controlled by a C-H⋯O IMHB. IMHB-directed remote CHB appeared operative in the C6 borylation of 3-aminoindazole (seven-membered IMHB) and C6 borylation of an osimertinib analogue where a pyrimidine IMHB creates the steric shield. This study informs researchers to evaluate not only inter- but also intramolecular noncovalent interactions as potential drivers of remote CHB regioselectivity.

20.
BMC Pregnancy Childbirth ; 21(1): 830, 2021 Dec 14.
Article in English | MEDLINE | ID: mdl-34906118

ABSTRACT

OBJECTIVE: To explore the experiences and perceptions of stillbirth among mothers from a tertiary medical centre in Kano, Northern Nigeria. DESIGN: Qualitative, interpretative. SETTING: Tertiary healthcare facility, Murtala Muhammad Specialist Hospital (MMSH), Kano, Northern Nigeria. SAMPLE: Mothers who had given birth to a liveborn baby at the MMSH in the prior 6 months (n = 31). In order to capture the experiences and perception of stillbirth within this cohort we approached mothers who had in a previous pregnancy experienced a stillbirth. Of the 31 who attended 16 had a previous stillbirth. METHODS: Semi-structured Focus Group Discussions, consisting of open-ended questions about stillbirth, beliefs, experiences and influences were held in MMSH, conducted over 1 day. RESULTS: Our findings highlight that this is a resource-poor tertiary facility serving an ever-growing population, increasing strain on the hospital and healthcare workers. Many of the participants highlighted needing permission from certain family members before accessing healthcare or medical treatment. We identified that mothers generally have knowledge on self-care during pregnancy, yet certain societal factors prevented that from being their priority. Judgement and blame was a common theme, yet a complex area entwined with traditions, superstitions and the pressure to procreate with many mothers described being made to feel useless and worthless if they did not birth a live baby. CONCLUSIONS: As access to healthcare becomes easier, there are certain traditions, family and social dynamics and beliefs which conflict with scientific knowledge and act as a major barrier to uptake of healthcare services. The findings highlight the need for investment in maternity care, appropriate health education and public enlightenment; they will help inform appropriate interventions aimed at reducing stigma around stillbirth and aide in educating mothers about the importance of appropriate health seeking behaviour. Stillbirths are occurring in this area of the world unnecessarily, globally there has been extensive research conducted on stillbirth prevention. This research has highlighted some of the areas which can be tackled by modifying existing successful interventions to work towards reducing preventable stillbirths.


Subject(s)
Mothers/psychology , Stillbirth/psychology , Family Relations/ethnology , Female , Focus Groups , Health Services Accessibility , Humans , Nigeria/ethnology , Pregnancy , Qualitative Research , Social Values/ethnology , Social Vulnerability
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