scRNA-seq profiling of human granulocytes reveals expansion of developmentally flexible neutrophil precursors with mixed neutrophil and eosinophil properties in asthma.

Neutrophils and eosinophils share common hematopoietic precursors and usually diverge into distinct lineages with unique markers before being released from their hematopoietic site, which is the bone marrow (BM). However, previous studies identified an immature Ly6g(+) Il-5Rα(+) neutrophil population in mouse BM, expressing both neutrophil and eosinophil markers suggesting hematopoietic flexibility. Moreover, others have reported neutrophil populations expressing eosinophil-specific cell surface markers in tissues and altered disease states, confusing the field regarding eosinophil origins, function, and classification. Despite these reports, it is still unclear whether hematopoietic flexibility exists in human granulocytes. To answer this, we utilized single-cell RNA sequencing (scRNA-seq) and CITE-seq to profile human BM and circulating neutrophils and eosinophils at different stages of differentiation and determine whether neutrophil plasticity plays role in asthmatic inflammation. We show that immature metamyelocyte neutrophils in humans expand during severe asthmatic inflammation and express both neutrophil and eosinophil markers. We also show an increase in tri-lobed eosinophils with mixed neutrophil and eosinophil markers in allergic asthma and that IL-5 promotes differentiation of immature blood neutrophils into tri-lobed eosinophilic phenotypes suggesting a mechanism of emergency granulopoiesis to promote myeloid inflammatory or remodeling response in patients with chronic asthma. By providing insights into unexpectedly flexible granulocyte biology and demonstrating emergency hematopoiesis in asthma, our results highlight the importance of granulocyte plasticity in eosinophil development and allergic diseases.

Molecular basis of differential HLA class I-restricted T cell recognition of a highly networked HIV peptide.

Cytotoxic-T-lymphocyte (CTL) mediated control of HIV-1 is enhanced by targeting highly networked epitopes in complex with human-leukocyte-antigen-class-I (HLA-I). However, the extent to which the presenting HLA allele contributes to this process is unknown. Here we examine the CTL response to QW9, a highly networked epitope presented by the disease-protective HLA-B57 and disease-neutral HLA-B53. Despite robust targeting of QW9 in persons expressing either allele, T cell receptor (TCR) cross-recognition of the naturally occurring variant QW9_S3T is consistently reduced when presented by HLA-B53 but not by HLA-B57. Crystal structures show substantial conformational changes from QW9-HLA to QW9_S3T-HLA by both alleles. The TCR-QW9-B53 ternary complex structure manifests how the QW9-B53 can elicit effective CTLs and suggests sterically hindered cross-recognition by QW9_S3T-B53. We observe populations of cross-reactive TCRs for B57, but not B53 and also find greater peptide-HLA stability for B57 in comparison to B53. These data demonstrate differential impacts of HLAs on TCR cross-recognition and antigen presentation of a naturally arising variant, with important implications for vaccine design.

Chemical Stabilization and Electrochemical Destabilization of the Iron Keggin Ion in Water.

The iron Keggin ion is identified as a structural building block in both magnetite and ferrihydrite, two important iron oxide phases in nature and in technology. Discrete molecular forms of the iron Keggin ion that can be both manipulated in water and chemically converted to the related metal oxides are important for understanding growth mechanisms, in particular, nonclassical nucleation in which cluster building units are preserved in the aggregation and condensation processes. Here we describe two iron Keggin ion structures, formulated as [Bi6FeO4Fe12O12(OH)12(CF3COO)10(H2O)2]3+ (Kegg-1) and [Bi6FeO4Fe12O12(OH)12(CF3COO)12]1+ (Kegg-2). Experimental and simulated X-ray scattering studies show indefinite stability of these clusters in water from pH 1-3. The tridecameric iron Keggin-ion core is protected from hydrolysis by a synergistic effect of the capping Bi3+ cations and the trifluoroacetate ligands that, respectively, bond to the iron and bridge to the bismuth. By introducing electrons to the aqueous solution of clusters, we achieve complete separation of bismuth from the cluster, and the iron Keggin ion rapidly converts to magnetite and/or ferrihydrite, depending on the mechanism of reduction. In this strategy, we take advantage of the easily accessible reduction potential and crystallization energy of bismuth. Reduction was executed in bulk by chemical means, by voltammetry, and by secondary effects of transmission electron microscopy imaging of solutions. Prior, we showed a less stable analogue of the iron Keggin cluster converted to ferrihydrite simply upon dissolution. The prior and currently studied clusters with a range of reactivity provide a chemical system to study molecular cluster to metal oxide conversion processes in detail.

Open conformers of HLA-F are high-affinity ligands of the activating NK-cell receptor KIR3DS1.

The activating natural killer (NK)-cell receptor KIR3DS1 has been linked to the outcome of various human diseases, including delayed progression of disease caused by human immunodeficiency virus type 1 (HIV-1), yet a ligand that would account for its biological effects has remained unknown. We screened 100 HLA class I proteins and found that KIR3DS1 bound to HLA-F, a result we confirmed biochemically and functionally. Primary human KIR3DS1(+) NK cells degranulated and produced antiviral cytokines after encountering HLA-F and inhibited HIV-1 replication in vitro. Activation of CD4(+) T cells triggered the transcription and surface expression of HLA-F mRNA and HLA-F protein, respectively, and induced binding of KIR3DS1. HIV-1 infection further increased the transcription of HLA-F mRNA but decreased the binding of KIR3DS1, indicative of a mechanism for evading recognition by KIR3DS1(+) NK cells. Thus, we have established HLA-F as a ligand of KIR3DS1 and have demonstrated cell-context-dependent expression of HLA-F that might explain the widespread influence of KIR3DS1 in human disease.

Spin crossover in iron(II) complexes with ferrocene-bearing triazole-pyridine ligands.

In the search for new multifunctional spin crossover molecular materials, here we describe the synthesis, crystal structures and magnetic and photomagnetic properties of the complexes trans-[Fe(Fc-tzpy)2(NCX)2]·CHCl3 where Fc-tzpy is the ferrocene-appended ligand 4-(2-pyridyl)-1H-1,2,3-triazol-1-ylferrocene, X = S (1) and X = Se (2). Both complexes display thermal- and light-induced (LIESST) spin crossover properties characterised by T1/2 = 85 and 168 K, ΔS = 55 and 66 J K(-1) mol(-1), ΔH = 4.7 and 11.1 kJ mol(-1) and TLIESST = 47 K and 39 K for1 and 2 respectively. The crystal structure of 1 and 2 measured at 275 K is consistent with the iron(ii) ion in the high-spin state while the crystal structure of at 120 K denotes the occurrence of complete transformation to the low-spin state.

El impacto de la detección de disfunción endotelial en la aterosclerosis: estudio mediante tomografía por emisión de positrones / Impact of the detection of endothelial dysfunction in atherosclerosis: Assessment by positron emission tomography

El endotelio juega un papel importante en la regulación del líquido intracelular, la permeabilidad vascular, en la modulación del tono vascular focal y la angiogénesis. La disfunción endotelial se manifiesta por la pérdida de la capacidad del endotelio de modular el comportamiento fisiológico del lecho vascular y actualmente se considera un marcador pronóstico de la enfermedad arterial coronaria. La relevancia de estudiar la disfunción endotelial radica en que ésta se ha observado en diversas patologías como diabetes mellitas (DM), dislipidemia, hipertensión arterial sistémica, tabaquismo o en enfermedades inmunológicas como síndrome antifosfolípido y lupus eritematoso sistémico. La Tomografía por Emisión de Positrones (PET) es un método no invasivo que permite cuantificar en términos absolutos el flujo miocárdico en reposo, esfuerzo y durante la estimulación adrenérgica, siendo considerado en la actualidad el estándar de oro para valorar la función endotelial. Por lo tanto el PET es una herramienta diagnóstica muy útil en identificar a los pacientes con disfunción endotelial y en evaluar la respuesta a la terapia administrada en enfermedades que se acompañen de ésta. Permitiendo un control óptimo y prevención de eventos adversos de estas enfermedades.

The endothelium plays an important role in the regulation of the intracellular fluid, vascular permeability, and modulation of vascular focal tone and angiogenesis. Endothelial dysfunction is manifested by the loss of the endothelium ability to modulate physiology changes in its vascular bed, and actually it is considered a prognostic marker of coronary artery disease. The relevance of assessing endothelial dysfunction relies in that it has been observed in different pathologies like DM, dyslipidemia, hypertension, tabaquism and in immunologic diseases like antiphospholipid syndrome and systemic lupus. PET is a non invasive method that allows the absolute quantification of myocardial blood flow during rest, stress and adrenergic stimulation, which allows to asses endothelial function. Therefore PET is a useful diagnostic technique to identify patients with endothelial dysfunction, and in the assessment of its response to administered therapy, allowing an optimal control and prevention of secondary adverse events of these diseases.

Importancia de la detección de viabilidad miocárdica: evaluación con tomografía por emisión de positrones con 18F-FDG / Value of the assessment of myocardial viability: evaluation with positron emission tomography 18F-FDG

It used to be thought that the consequences of coronary artery disease were final, and that the prognosis of the patient was limited to the extent of the ventricular dysfunction. This paradigm changed radically when the concept of hibernating myocardium was introduced, which states the existence of tissue that can regain contractile function after being re-vascularized. This introduced a new concept in cardiology: myocardial viability. This work presents a clear example of the importance of detecting myocardial viability in selected patients, due to the impact not only in treatment but in prognosis as well. It is also emphasized that positron emission tomography (PET) is the gold standard method to detect myocardial viability.

[Endothelial function assessment by positron emission tomography in patients with hypercholesterolemia]. / Estudio de la función endotelial mediante tomografía por emisión de positrones en pacientes con hipercolesterolemia.

UNLABELLED: Hypercholesterolemia prompts to endothelial dysfunction (ED) and ED predisposes to atherogenesis. ED appears early in the course of atherogenesis and it is considered a coronary artery disease (CAD) marker. OBJECTIVES: To assess endothelial function (EF) using Positron Emission Tomography (PET) in asymptomatic patients with recent dyslipidemia diagnosis and without history of ischemic heart disease and previous hypolipemiant treatment. MATERIAL AND METHODS: Fourteen asymptomatic patients with recent dyslipidemia diagnosis (< 6 months) were studied by obtaining a lipid profile, blood glucose, and a three phase 13N-ammonia PET scan: rest, cold pressor test (CPT) and pharmacologic stress with adenosine. EF was assessed by calculating the coronary flow reserve (CFR), endothelial-dependant vasodilatation index (EDVI), and coronary blood flow increase percentage in CPT (% Delta CF). RESULTS: 79% of patients with dyslipidemia had ED and all their values were lower than those previously published as normal: rest coronary flow 0.44 +/- 0.12 vs 0.57 +/- 0.147 (p = 0.002), CPT coronary flow 0.57 +/- 0.17 vs 0.88 +/- 0.26 (p = 0.001), stress coronary flow 1.24 +/- 0.05 vs 1.81 +/- 0.35 (p = 0.005), EDVI 1.28 +/- 0.25 vs 1.53 +/- 0.24 (p 0.017), CRF 2.79 +/- 0.94 vs 3.15 +/- 0.48 (p 0.198) and % Delta CF 29.08 +/- 24.62% vs 53 +/- 24.60% (p 0.022). CONCLUSIONS: Asymptomatic patients in early stages of dyslipidemia showed a greater ED prevalence that was detected by 13N-ammonia PET scan.

Tomografía computada multidetector de arterias coronarias: estado del arte. Parte II: Aplicaciones clínicas / Multidetector computed tomography of coronary arteries: state of the art. Second part: clinical applications

At the beginning of the evaluation of Coronary Artery Disease (CAD), Coronary Multidetector Computed Tomography (MDCT) was exclusively used to detect calcified plaques in coronary arteries through the Calcium Score, whose value by itself is limited. Nowadays, thanks to the technological advancements, potential clinical applications, with this method, include detection of coronary arterial stenosis, assessment of coronary bridges, and evaluation of anomalous coronaries. The intraluminal coronary stent evaluation is not possible yet, but this might become possible with the new-generation scanners. At the moment, the published results seem to be promising, nonetheless, the enthusiasm generated by this method should be accompanied by adequate training, as well as by its validation and certification.

Estudio de la función endotelial mediante tomografía por emisión de positrones en pacientes con hipercolesterolemia / Endothelial function assessment by positron emission tomography in patients with hypercholesterolemia

Hypercholesterolemia prompts to endothelial dysfunction (ED) and ED predisposes to atherogenesis. ED appears early in the course of atherogenesis and it is considered a coronary artery disease (CAD) marker. OBJECTIVES: To assess endothelial function (EF) using Positron Emission Tomography (PET) in asymptomatic patients with recent dyslipidemia diagnosis and without history of ischemic heart disease and previous hypolipemiant treatment. MATERIAL AND METHODS: Fourteen asymptomatic patients with recent dyslipidemia diagnosis (< 6 months) were studied by obtaining a lipid profile, blood glucose, and a three phase 13N-ammonia PET scan: rest, cold pressor test (CPT) and pharmacologic stress with adenosine. EF was assessed by calculating the coronary flow reserve (CFR), endothelial-dependant vasodilatation index (EDVI), and coronary blood flow increase percentage in CPT (% Delta CF). RESULTS: 79% of patients with dyslipidemia had ED and all their values were lower than those previously published as normal: rest coronary flow 0.44 +/- 0.12 vs 0.57 +/- 0.147 (p = 0.002), CPT coronary flow 0.57 +/- 0.17 vs 0.88 +/- 0.26 (p = 0.001), stress coronary flow 1.24 +/- 0.05 vs 1.81 +/- 0.35 (p = 0.005), EDVI 1.28 +/- 0.25 vs 1.53 +/- 0.24 (p 0.017), CRF 2.79 +/- 0.94 vs 3.15 +/- 0.48 (p 0.198) and % Delta CF 29.08 +/- 24.62% vs 53 +/- 24.60% (p 0.022). Conclusions: Asymptomatic patients in early stages of dyslipidemia showed a greater ED prevalence that was detected by 13N-ammonia PET scan.

Modelo de estudio mediante microPET para la evaluación del metabolismo glucolítico en el miocardio de rata con 18F-FDG. Experiencia inicial en México / A method designed for the assessment of myocardial metabolism in rats with 18F-FDG using small-animal-PET. Initial experience in Mexico

PURPOSE: To standarize an acquisition protocol for the study of myocardial metabolism in adult rats. MATERIAL AND METHODS: Three Wistar adult male rats were studied in three different protocols: no fasting group, fasting group over a period of 12 hr before the study with only water provided ad libitum, and fasting group by the same time receiving an oral 50% glucose solution. Thirty-minute acquisition images were obtained with a micro-PET, thirty and sixty minutes after the administration of 370-555 MBq 18F-FDG. Comparative and visual analysis were performed by two experts in the field. RESULTS: Eigtheen studies were analyzed, six per group. The best images were those of the first group, especially those taken at 60 minutes after the 18F-FDG administration. CONCLUSION: It is possible to establish the non-fasting protocol for the assessment of myocardial metabolism to be used in the future for the myocardial viability evaluation in ischemic cardiopathy.

2-Aza-1,3-butadiene derivatives featuring an anthracene or pyrene unit: highly selective colorimetric and fluorescent signaling of Cu2+ cation.

[Structure: see text] A new probe based on an anthryl derivative bearing an azadiene side chain selectively senses Cu2+ in acetonitrile through two different channels: the yellow-to-orange color change and a remarkable enhancement of the fluorescence, whereas the pyrenyl analogous behaves as a fluorescent sensor for Cu2+ and Hg2+ in aqueous environment.

Synthesis and cytotoxic evaluation of new derivatives of the marine alkaloid variolin B.

The marine alkaloid variolin B 2 and eight synthetic derivatives with different substituents at positions C-5 and C-7 have been tested in a panel of sixteen human tumor cell lines to evaluate their cytotoxic potential.

[Fibroepithelial polyp of the ureter. Report of one case]. / Pólipo ureteral. Presentación de un caso.

OBJECTIVES: To report the rare case of a patient with a ureteral polyp. METHODS: We describe the case of a 55-year-old female patient receiving care at the Celia Sanchez Manduley University Hospital in Manzanillo, Cuba, who was fortuitously diagnosed of a fibroepithelial polyp of the right ureter during the work up and treatment of an ovarian tumor. RESULTS: This case is the first of its kind in this hospital after 22 years, which confirms the rarity of ureteral tumors, specifically those of benign etiology. The absence of symptoms, specifically hematuria and pain, does not correspond to the reviewed articles. The chosen treatment was exeresis of the polyp at its base and frozen biopsy, followed by re-establishment of the urinary passage, as various authors recommend. Currently the endoscopical approach is recommended for its multiple advantages. CONCLUSIONS: We conclude that this disease is very rare, may have a symptomatic course and the treatment of choice is surgery with very good results.

A novel cyclo-oxygenase-2 inhibitor modulates catabolic and antiinflammatory mediators in osteoarthritis.

ITB (6-(p-bromophenyl)amino-7-(p-chlorophenyl)indazolo[2',3':1,5]-1,2,4-triazolo[4,3-a]-1,3,5-benzotriazepine) is a novel inhibitor of cyclo-oxygenase-2 (COX-2) with antiinflammatory activity in animal models. In the present study, we investigated the effect of this compound on the production of catabolic or antiinflammatory mediators in osteoarthritis (OA) cartilage. In OA cartilage explants, ITB inhibited the production of prostaglandin E(2) (PGE(2)), tumour necrosis factor-alpha (TNF-alpha) and matrix metalloproteinase-13 (MMP-13) in a concentration-dependent manner, whereas nitrite was partially reduced. On the contrary, ITB increased the production of interleukin (IL)-10 and the expression of heme oxygenase-1 (HO-1). ITB inhibited the production of catabolic mediators at concentrations able to increase IL-10 and HO-1 in OA cartilage, suggesting that this compound may be useful in the prevention of cartilage degradation.

A novel indazolo-triazolo-benzotriazepine exerts anti-inflammatory effects by inhibition of cyclooxygenase-2 activity and nitric oxide synthase-2 expression.

We have studied the anti-inflammatory activity of (6-(p-bromophenyl)amino-7-(p-chlorophenyl)indazolo[2',3':1,5]-1,2,4-triazolo[4,3-a]-1,3,5-benzotriazepine (ITB), prepared by solid-phase synthesis. This novel compound reduced the production of nitrite and PGE(2) in RAW 264.7 macrophages stimulated with lipopolysaccharide in a concentration-dependent manner. The first effect was dependent on inhibition of nitric oxide synthase-2 (NOS-2) protein expression although ITB did not modify nuclear factor-kappa B (NF-kappa B)-DNA binding. In addition, this compound inhibited cyclooxygenase-2 (COX-2) activity, which was also observed in aspirin-treated human monocytes. The anti-inflammatory effects of ITB were demonstrated in the carrageenan-induced mouse paw oedema, where this compound inhibited swelling and PGE(2) levels in inflamed paws but not in stomachs, in contrast to the dual COX-1/COX-2 inhibitor indomethacin. Inhibition of COX-2 activity and NOS-2 protein expression was confirmed in vivo using the zymosan-injected mouse air pouch model. These results suggest that synthesis of fused indazolo bis(guanidines) is a useful approach in the search for new anti-inflammatory agents.

Carbodiimide-mediated preparation of the tricyclic pyrido[3',2':4,5]pyrrolo[1,2-c]pyrimidine ring system and its application to the synthesis of the potent antitumoral marine alkaloid variolin B and analog.

A total synthesis of the marine alkaloid variolin B has been completed in 13 steps in an overall yield of 6.5% from 3-formyl-4-methoxypyridine. Our approach is based on the sequential formation of the 7-azaindole ring, the tricyclic pyrido[3',2':4,5]pyrrolo[1,2-c]pyrimidine ring system, and finally installation of the 2-aminopyrimidine ring at C5. The required 7-azaindole ring appropriately substituted is formed by a modified indole synthesis involving a nitrene insertion process (two steps). Formation of the annelated pyrimidine ring is achieved by two routes both involving a carbodiimide-mediated cyclization process, which allow incorporation of the amine functionality at C9 of the core tricyclic (six steps). Installation of the northeast 2-aminopyrimidine ring at C5 is performed using the Bredereck protocol (three steps). Ultimate, thermal decarboxylation with concomitant O-methyl deprotection and further N-benzyl deprotection by the action of triflic acid completed the synthesis of the target natural product variolin B.