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1.
Nano Lett ; 24(19): 5824-5830, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38712765

RESUMEN

Boroxine- and borazine-cage analogs to C20, C60, and C70 were calculated and compared in terms of structure, strain indicators, and physical properties relevant to nanoscale applications. The results show C60 and C70 type cages are less strained than the smaller congener, primarily due to minimized bending in the B-arylene-B segments. The smallest cage calculated has a diameter of 2.4 nm, which increases up to 4.9 nm by either variation of the polyhedron (C20 < C60 < C70-type cage) or organic spacer elongation between boron centers. All calculated cages are porous (apertures ranging from 0.6 to 1.9 nm). Molecular electrostatic potential and Hirshfeld population analysis revealed both nucleophilic and electrophilic sites in the interior and exterior cage surfaces. HOMO-LUMO gaps range from 3.98 to 4.89 eV and 5.10-5.18 eV for the boroxine- and borazine-cages, respectively. Our findings provide insights into the design and properties of highly porous boroxine and borazine cages for nanoscience.

2.
Proc Natl Acad Sci U S A ; 118(31)2021 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-34326259

RESUMEN

Proinflammatory activation of macrophages in metabolic tissues is critically important in the induction of obesity-induced metaflammation. Here, we demonstrate that the soluble mannose receptor (sMR) plays a direct functional role in both macrophage activation and metaflammation. We show that sMR binds CD45 on macrophages and inhibits its phosphatase activity, leading to an Src/Akt/NF-κB-mediated cellular reprogramming toward an inflammatory phenotype both in vitro and in vivo. Remarkably, increased serum sMR levels were observed in obese mice and humans and directly correlated with body weight. Importantly, enhanced sMR levels increase serum proinflammatory cytokines, activate tissue macrophages, and promote insulin resistance. Altogether, our results reveal sMR as regulator of proinflammatory macrophage activation, which could constitute a therapeutic target for metaflammation and other hyperinflammatory diseases.


Asunto(s)
Regulación de la Expresión Génica/efectos de los fármacos , Activación de Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Receptor de Manosa/química , Proteínas de la Membrana/farmacología , Alimentación Animal , Animales , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Dieta Alta en Grasa , Microbioma Gastrointestinal , Inflamación , Activación de Macrófagos/fisiología , Masculino , Receptor de Manosa/metabolismo , Ratones , Ratones Noqueados , Distribución Aleatoria
3.
Angew Chem Int Ed Engl ; 63(31): e202400227, 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-38317632

RESUMEN

2-tetrelavinylidenes (C=EH2; E=Si, Ge) are according to quantum chemical studies the least stable isomers on the [E,C,2H] potential energy hypersurface isomerizing easily via the trans-bent tetrelaacetylenes HE≡CH to the thermodynamically most stable 1-tetrelavinylidenes (E=CH2). Consequently, experimental studies on 2-tetrelavinylidenes (C=ER2) and their derivatives are lacking. Herein we report experimental and theoretical studies of the first N-heterocyclic carbene (NHC) supported 2-silavinylidene (NHC)C=SiBr(Tbb) (1-Si: NHC=C[N(Dipp)CH]2, Dipp=2,6-diisopropylphenyl, Tbb=2,6-bis[bis(trimethylsilyl)methyl]-4-tert-butylphenyl) and the isovalent 2-germavinylidenes (NHC)C=GeBr(R) (1-Ge, 1-GeMind: R=Tbb, Mind (1,1,3,3,5,5,7,7-octamethyl-s-hydrindacene-4-yl)). The NHC-supported 2-tetrelavinylidenes were obtained selectively from the 1,2-dibromoditetrelenes (E)-(R)BrE=EBr(R) using the diazoolefin (NHC)CN2 as vinylidene transfer reagent. 1-E (E=Si, Ge) have a planar vinylidene core, a bent-dicoordinated vinylidene carbon atom (CVNL), a very short E=CVNL bond and an almost orthogonal orientation of the NHC five-membered ring to the vinylidene core. Quantum chemical analysis of the electronic structures of 1-E suggest a significantly bent 1-tetrelaallene and tetrelyne character. NMR studies shed light into the dynamics of 1-E involving NHC-rotation around the CVNL-CNHC bond with a low activation barrier. Furthermore, the synthetic potential of 1-E is demonstrated by the synthesis and full characterization of the unprecedented NHC-supported bromogermynes BrGe=C(EBr2Tbb)(NHC) (2-SiGe: E=Si; 2-GeGe: E=Ge).

4.
Chemistry ; 29(64): e202302653, 2023 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-37616378

RESUMEN

Developing an atomistic understanding of ionizing radiation induced changes to organic materials is necessary for intentional design of greener and more sustainable materials for radiation shielding and detection. Cocrystals are promising for these purposes, but a detailed understanding of how the specific intermolecular interactions within the lattice upon exposure to radiation affect the structural stability of the organic crystalline material is unknown. This study evaluates atomistic-level effects of γ radiation on both single- and multicomponent organic crystalline materials and how specific noncovalent interactions and packing within the crystalline lattice enhance structural stability. Dose studies were performed on all crystalline systems and evaluated via experimental and computational methods. Changes in crystallinity were evaluated by p-XRD and free radical formation was analyzed via EPR spectroscopy. Type of intermolecular interactions and packing within the crystal lattice was delineated and related to the specific free radical species formed and the structural integrity of each material. Periodic DFT and HOMO-LUMO surface mapping calculations provided atomistic-level identifications of the most probable sites for the radicals formed upon exposure to γ radiation and relate intermolecular interactions and molecular packing within the crystalline lattice to experimental results.

5.
BMC Public Health ; 23(1): 2475, 2023 12 11.
Artículo en Inglés | MEDLINE | ID: mdl-38082349

RESUMEN

BACKGROUND: People with profound and multiple intellectual disabilities (PMID) have high and intensive support needs that ordinarily place significant strain on family carers. This was further heightened by the removal of many external supports during the COVID-19 pandemic. We sought to explore the experiences of family carers of people with PMID during the COVID-19 pandemic and understand what the longer-term impact might be on their lives. METHODS: Focus group interviews (n = 32) were conducted with family carers (n = 126) from the four countries of the UK and the Republic of Ireland. Participants were asked questions relating to their experiences of the COVID-19 pandemic, coping strategies, and challenges faced. All focus groups were conducted using the online platform, Zoom. These were audio recorded, transcribed verbatim and analysed employing inductive thematic analysis. FINDINGS: Three main themes were generated from the data including (1.0) COVID-19 as a double-edged sword (2.0), The struggle for support (3.0), Constant nature of caring. These included 11 subthemes. (1.1) 'COVID-19 as a catalyst for change', (1.2) 'Challenges during COVID-19: dealing with change', (1.3) 'Challenges during COVID-19: fear of COVID-19', (1.4); 'The online environment: the new normal' (2.1) 'Invisibility of male carers', (2.2) 'Carers supporting carers', (2.3) 'The only service you get is lip service: non-existent services', (2.4); 'Knowing your rights' (3.1) 'Emotional response to the caring role: Feeling devalued', (3.2) 'Emotional response to the caring role: Desperation of caring', (3.3) 'Multiple demands of the caring role.' CONCLUSIONS: The COVID-19 pandemic presented immense challenges to family carers of people with PMID but also provided some opportunities. Families had already struggled to receive many of the supports and services to which they were entitled to only to have these removed at the onset of the pandemic. The experiences of male carers have been largely absent from the literature with this research showing they want to be included in decision making and require tailored support services. Service providers should see the end of the COVID-19 pandemic as providing opportunity to re-examine current provision and design services with family carers. As the direct threat from COVID-19 diminishes and the experiences of those who lived through this period come to the fore, there is a need to re-examine current models and provision of support to family carers to better meet their needs.


Asunto(s)
COVID-19 , Discapacidad Intelectual , Humanos , Masculino , Cuidadores/psicología , Pandemias , Discapacidad Intelectual/epidemiología , Investigación Cualitativa , Reino Unido/epidemiología , Familia/psicología
6.
Am J Perinatol ; 40(14): 1529-1536, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-34704241

RESUMEN

OBJECTIVE: In 2014, the American Academy of Pediatrics (AAP) changed its policy on the use of respiratory syncytial virus immunoprophylaxis (RSV-IP) so that RSV-IP was no longer recommended for use among infants without other medical conditions born >29 weeks of gestational age (wGA). This study examines 10-year trends in RSV-IP and RSV hospitalizations among term infants and preterm infants born at 29 to 34 wGA, including the 5 RSV seasons before and 5 RSV seasons after the AAP guidance change. STUDY DESIGN: A retrospective observational cohort study of a convenience sample of infants less than 6 months of age during RSV season (November-March) born between July 1, 2008, and June 30, 2019, who were born at 29 to 34 wGA (preterm) or >37 wGA (term) in the IBM MarketScan Commercial and Multi-State Medicaid databases. We excluded infants with medical conditions that would independently qualify them for RSV-IP. We identified RSV-IP utilization along with RSV and all-cause bronchiolitis hospitalizations during each RSV season. A difference-in-difference model was used to determine if there was a significant change in the relative rate of RSV hospitalizations following the 2014 policy change. RESULTS: There were 53,535 commercially insured and 85,099 Medicaid-insured qualifying preterm infants and 1,111,670 commercially insured and 1,492,943 Medicaid-insured qualifying term infants. Following the 2014 policy change, RSV-IP utilization decreased for all infants, while hospitalization rates tended to increase for preterm infants. Rate ratios comparing preterm to term infants also increased. The relative rate for RSV hospitalization for infants born at 29 to 34 wGA increased significantly for both commercially and Medicaid-insured infants (1.95, 95% CI: 1.67-2.27, p <0.001; 1.70, 95% CI: 1.55-1.86, p <0.001, respectively). Findings were similar for all-cause bronchiolitis hospitalizations. CONCLUSION: We found that the previously identified increase in RSV hospitalization rates among infants born at 29 to 34 wGA persisted for at least 5 years following the policy change. KEY POINTS: · Immunoprophylaxis rates decreased after the 2014 American Academy of Pediatrics guidelines update.. · Rate of RSV hospitalization increased among preterm infants after the 2014 AAP guidelines update.. · Increase in RSV hospitalization persisted for at least 5 years after AAP guidelines update..


Asunto(s)
Bronquiolitis , Infecciones por Virus Sincitial Respiratorio , Virus Sincitial Respiratorio Humano , Lactante , Femenino , Recién Nacido , Humanos , Niño , Estados Unidos/epidemiología , Recien Nacido Prematuro , Infecciones por Virus Sincitial Respiratorio/epidemiología , Infecciones por Virus Sincitial Respiratorio/prevención & control , Infecciones por Virus Sincitial Respiratorio/tratamiento farmacológico , Antivirales/uso terapéutico , Estudios Retrospectivos , Hospitalización , Edad Gestacional , Palivizumab/uso terapéutico
7.
Appl Surf Sci ; 6342023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37389357

RESUMEN

Laparoscopes can suffer from fogging and contamination difficulties, resulting in a reduced field of view during surgery. A series of diamond-like carbon films, doped with SiO, were produced by pulsed laser deposition for evaluation as biocompatible, antifogging coatings. DLC films doped with SiO demonstrated hydrophilic properties with water contact angles under 40°. Samples subjected to plasma cleaning had improved contact angle results, with values under 5°. Doping the DLC films with SiO led to an average 40% decrease in modulus and 60% decrease in hardness. Hardness of the doped films, 12.0 - 13.2 GPa, was greater than that of the uncoated fused silica substrate, 9.2 GPa. The biocompatibility was assessed through CellTiter-Glo assays, with the films demonstrating statistically similar levels of cell viability when compared to the control media. The absence of ATP released by blood platelets in contact with the DLC coatings suggests in vivo hemocompatibility. The SiO doped films displayed improved transparency levels in comparison to undoped films, achieving up to an average of 80% transmission over the visible spectrum and an attenuation coefficient of 1.1 × 104 cm-1 at the 450 nm wavelength. The SiO doped DLC films show promise as a method of fog prevention for laparoscopes.

8.
J Craniofac Surg ; 34(7): 1978-1984, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37449578

RESUMEN

Orofacial clefts (OFC) remain among the most prevalent congenital abnormalities worldwide. In the United States in 2010 to 2014, 16.2 of 10,000 live births are born with OFC compared with 23.6 of 10,000 in Alta Verapaz, Guatemala in 2012. Demographics and cleft severity scores were retrospectively gathered from 514 patients with isolated OFC at the Children's Hospital of Philadelphia scheduled for surgery from 2012 to 2019 and from 115 patients seen during surgical mission trips to Guatemala City from 2017 to 2020. Risk factors were also gathered prospectively from Guatemalan families. The Guatemalan cohort had a significantly lower prevalence of cleft palate only compared with the US cohort, which may be a result of greater cleft severity in the population or poor screening and subsequent increased mortality of untreated cleft palate. Of those with lip involvement, Guatemalan patients were significantly more likely to have complete cleft lip, associated cleft palate, and right-sided and bilateral clefts, demonstrating an increased severity of Guatemalan cleft phenotype. Primary palate and lip repair for the Guatemalan cohort occurred at a significantly older age than that of the US cohort, placing Guatemalan patients at increased risk for long-term complications such as communication difficulties. Potential OFC risk factors identified in the Guatemalan cohort included maternal cooking-fire and agricultural chemical exposure, poor prenatal vitamin intake, poverty, and risk factors related to primarily corn-based diets. OFC patients who primarily rely on surgical missions for cleft care would likely benefit from more comprehensive screening and investigation into risk factors for more severe OFC phenotypes.

9.
Cleft Palate Craniofac J ; 60(8): 1010-1020, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-35711155

RESUMEN

OBJECTIVE: To determine the impact of illustrated postoperative instructions on patient-caregiver knowledge and retention. DESIGN: Prospective study with all participants receiving an educational intervention. SETTING: Pediatric plastic surgical missions in Guatemala City, Guatemala, between 2019 and 2020. PARTICIPANTS: A total of 63 majority-indigenous Guatemalan caregivers of patients receiving cleft lip and/or palate surgery. INTERVENTION: Illustrated culturally appropriate postoperative care instructions were iteratively developed and given to caregivers who were surveyed on illustration-based and text-based information at preoperative, postoperative, and four-week follow-up time points. MAIN OUTCOME MEASURE: Postoperative care knowledge of illustration-based versus text-based information as determined by the ability to answer 11 illustration- and 8 text-based all-or-nothing questions, as well as retention of knowledge as determined by the same survey given at four weeks follow-up. RESULTS: Scores for illustration-based and text-based information both significantly increased after caregivers received the postoperative instructions (+13.30 ± 3.78 % SE, + 11.26 ± 4.81 % SE; P < .05). At follow-up, scores were unchanged for illustration-based (-3.42 ± 4.49 % SE, P > .05), but significantly lower for text-based information (-28.46 ± 6.09 % SE, P < .01). Retention of text-based information at follow-up correlated positively with education level and Spanish literacy, but not for illustration-based. CONCLUSIONS: In the setting of language and cultural barriers on a surgical mission, understanding of illustration-based and text-based information both increased after verbal explanation of illustrated postoperative instructions. Illustration-based information was more likely to be retained by patient caregivers after four weeks than text-based information, the latter of which correlated with increased education and literacy.


Asunto(s)
Labio Leporino , Fisura del Paladar , Misiones Médicas , Humanos , Niño , Labio Leporino/cirugía , Fisura del Paladar/cirugía , Estudios Prospectivos
10.
Angew Chem Int Ed Engl ; 62(35): e202308350, 2023 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-37365138

RESUMEN

Mechanochemistry afforded a photoactive cocrystal via coexisting (B)O-H⋅⋅⋅N hydrogen bonds and B←N coordination. Specifically, solvent-free mechanochemical ball mill grinding and liquid-assisted grinding of a boronic acid and an alkene resulted in mixtures of hydrogen-bonded and coordinated complexes akin to mixtures of noncovalent complexes that can be obtained in solution in equilibria processes. The alkenes of the hydrogen-bonded assembly undergo an intermolecular [2+2] photodimerization in quantitative conversion, effectively reporting the outcome of the self-assembly processes. Our results suggest that interplay involving noncovalent bonds subjected to mechanochemical conditions can lead to functional solids where, in the current case, the structure composed of the weaker hydrogen bonding interactions predominates.

11.
Antimicrob Agents Chemother ; 66(5): e0013922, 2022 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-35475635

RESUMEN

The polymyxins display excellent in vitro antimicrobial activity against most Enterobacterales, Pseudomonas aeruginosa, and Acinetobacter baumannii isolates, but their clinical utility has been limited because of class-specific toxicity problems. Therefore, new polymyxin analogs with improved safety properties are needed to combat serious infections caused by resistant Gram-negative pathogens. MRX-8 is a novel polymyxin B analog that displays reduced toxicity in in vitro and animal assays and is currently being evaluated in a phase 1 clinical trial. In this nonclinical study, the in vitro potency and spectrum of MRX-8 and comparators were evaluated against a large set of Gram-negative clinical isolates collected in the United States in 2017 to 2020. MRX-8, colistin, and polymyxin B exhibited nearly identical antimicrobial activities against the Enterobacterales, Pseudomonas aeruginosa, and Acinetobacter baumannii isolate sets. MRX-8 MIC50 and MIC90 values were 0.12 and 0.25 mg/L, respectively, for the set of Enterobacterales isolates not intrinsically resistant to colistin and 0.5 and 1 mg/L, respectively, against both the A. baumannii and P. aeruginosa isolate sets. All three polymyxin-class compounds retained activity against meropenem-resistant and multidrug-resistant isolate subsets but were inactive against isolates displaying acquired or intrinsic resistance to polymyxins. These results support the continued development of MRX-8 to treat serious Gram-negative infections.


Asunto(s)
Acinetobacter baumannii , Polimixinas , Animales , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Colistina/farmacología , Farmacorresistencia Bacteriana Múltiple , Bacterias Gramnegativas , Pruebas de Sensibilidad Microbiana , Polimixina B/farmacología , Polimixinas/farmacología , Pseudomonas aeruginosa
12.
J Antimicrob Chemother ; 77(10): 2642-2649, 2022 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-35897129

RESUMEN

BACKGROUND: Zidebactam, a bicyclo-acyl hydrazide ß-lactam 'enhancer' antibiotic, in combination with cefepime (WCK 5222) is under clinical development for the treatment of resistant Gram-negative infections. OBJECTIVES: To evaluate the in vitro activity of cefepime/zidebactam and comparators against 24 220 Gram-negative bacteria. METHODS: Organisms were consecutively collected in 2018-19 from 137 medical centres located in the USA (n = 9140), Western Europe (W-EU; n = 5929), Eastern Europe (E-EU; n = 3036), the Asia-Pacific region (APAC; n = 3791) and Latin America (LATAM; n = 2324). The isolates were susceptibility tested using the broth microdilution method as part of the SENTRY Program. Cefepime/zidebactam was tested at a 1:1 ratio. RESULTS: Cefepime/zidebactam was highly active against Enterobacterales (MIC50/90 0.03/0.25 mg/L; 99.9% inhibited at ≤8 mg/L) and retained potent activity against carbapenem-resistant Enterobacterales (CRE) isolates (97.8% inhibited at ≤8 mg/L). CRE rates varied widely from 1.1% in the USA to 1.9% in W-EU, 3.6% in APAC and 14.6% in E-EU (3.9% overall). The most common carbapenemase genes observed overall were blaKPC (37.6% of CRE), blaOXA-48-like (30.0%) and blaNDM (23.8%). Resistance to ceftazidime/avibactam among CRE was elevated in APAC (64.8%), E-EU (25.5%) and LATAM (20.7%). Against Pseudomonas aeruginosa, cefepime/zidebactam inhibited 99.2% of isolates at ≤8 mg/L and susceptibility to ceftazidime/avibactam and ceftolozane/tazobactam was lowest in E-EU (83.9% and 82.0%, respectively). Cefepime/zidebactam exhibited good activity against Stenotrophomonas maltophilia (80.0% inhibited at ≤8 mg/L) and Burkholderia cepacia (89.4% inhibited at ≤8 mg/L). CONCLUSIONS: Cefepime/zidebactam demonstrated potent in vitro activity against a large worldwide collection of contemporary clinical isolates of Gram-negative bacteria.


Asunto(s)
Ceftazidima , Lactamas , Antibacterianos/farmacología , Compuestos de Azabiciclo/farmacología , Carbapenémicos , Cefepima/farmacología , Ceftazidima/farmacología , Cefalosporinas/farmacología , Ciclooctanos , Enterobacteriaceae , Bacterias Gramnegativas , Hidrazinas , Pruebas de Sensibilidad Microbiana , Piperidinas , Pseudomonas aeruginosa , Tazobactam
13.
PLoS Pathog ; 16(9): e1008799, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32898164

RESUMEN

Professional antigen-presenting cells (APCs), like macrophages (Mϕs) and dendritic cells (DCs), are central players in the induction of natural and vaccine-induced immunity to malaria, yet very little is known about the interaction of SPZ with human APCs. Intradermal delivery of whole-sporozoite vaccines reduces their effectivity, possibly due to dermal immunoregulatory effects. Therefore, understanding these interactions could prove pivotal to malaria vaccination. We investigated human APC responses to recombinant circumsporozoite protein (recCSP), SPZ and anti-CSP opsonized SPZ both in monocyte derived MoDCs and MoMϕs. Both MoDCs and MoMϕs readily took up recCSP but did not change phenotype or function upon doing so. SPZ are preferentially phagocytosed by MoMϕs instead of DCs and phagocytosis greatly increased after opsonization. Subsequently MoMϕs show increased surface marker expression of activation markers as well as tolerogenic markers such as Programmed Death-Ligand 1 (PD-L1). Additionally they show reduced motility, produce interleukin 10 and suppressed interferon gamma (IFNγ) production by antigen specific CD8+ T cells. Importantly, we investigated phenotypic responses to SPZ in primary dermal APCs isolated from human skin explants, which respond similarly to their monocyte-derived counterparts. These findings are a first step in enhancing our understanding of pre-erythrocytic natural immunity and the pitfalls of intradermal vaccination-induced immunity.


Asunto(s)
Células Presentadoras de Antígenos/inmunología , Macrófagos/inmunología , Malaria/inmunología , Plasmodium berghei/inmunología , Proteínas Protozoarias/inmunología , Piel/inmunología , Esporozoítos/inmunología , Animales , Células Cultivadas , Femenino , Humanos , Macrófagos/parasitología , Malaria/parasitología , Ratones , Piel/parasitología
14.
Chemistry ; 28(37): e202200978, 2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35507693

RESUMEN

A method to rapidly diversify the molecules formed in organic crystals is introduced, with aryl nitriles playing a novel dual role as both hydrogen-bond acceptors and modifiable organic groups. The discovery of coexisting supramolecular synthons in the same crystal is also described. The general concept is demonstrated by using a bis(aryl nitrile) alkene that undergoes a hydrogen-bond-directed intermolecular [2+2] photodimerization to form a tetra(aryl nitrile)cyclobutane. The product is readily converted by click reactivity to a tetra(aryl tetrazole) and by hydrolysis to a tetra(aryl carboxylic acid). The integration of aryl nitriles into solid-state reactions opens broad avenues to post-modify products formed in crystalline solids for rapid diversification.


Asunto(s)
Ciclobutanos , Nitrilos , Ácidos Carboxílicos/química , Hidrógeno , Enlace de Hidrógeno , Nitrilos/química
15.
Chemistry ; 28(25): e202104604, 2022 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-35274391

RESUMEN

Cocrystallizations of diboronic acids [1,3-benzenediboronic acid (1,3-bdba), 1,4-benzenediboronic acid (1,4-bdba) and 4,4'-biphenyldiboronic acid (4,4'-bphdba)] and bipyridines [1,2-bis(4-pyridyl)ethylene (bpe) and 1,2-bis(4-pyridyl)ethane (bpeta)] generated the hydrogen-bonded 1 : 2 cocrystals [(1,4-bdba)(bpe)2 ] (1), [(1,4-bdba)(bpeta)2 ] (2), [(1,3-bdba)(bpe)2 (H2 O)2 ] (3) and [(1,3-bdba)(bpeta)2 (H2 O)] (4), wherein 1,3-bdba involved hydrated assemblies. The linear extended 4,4'-bphdba exhibited the formation of 1 : 1 cocrystals [(4,4'-bphdba)(bpe)] (5) and [(4,4'-bphdba-me)(bpeta)] (6). For 6, a hemiester was generated by an in-situ linker transformation. Single-crystal X-ray diffraction revealed all structures to be sustained by B(O)-H⋅⋅⋅N, B(O)-H⋅⋅⋅O, Ow -H⋅⋅⋅O, Ow -H⋅⋅⋅N, C-H⋅⋅⋅O, C-H⋅⋅⋅N, π⋅⋅⋅π, and C-H⋅⋅⋅π interactions. The cocrystals comprise 1D, 2D, and 3D hydrogen-bonded frameworks with components that display reactivities upon cocrystal formation and within the solids. In 1 and 3, the C=C bonds of the bpe molecules undergo a [2+2] photodimerization. UV radiation of each compound resulted in quantitative conversion of bpe into cyclobutane tpcb. The reactivity involving 1 occurred via 1D-to-2D single-crystal-to-single-crystal (SCSC) transformation. Our work supports the feasibility of the diboronic acids as formidable structural and reactivity building blocks for cocrystal construction.

16.
FASEB J ; 35(2): e21331, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33476078

RESUMEN

Type 2 immunity plays an essential role in the maintenance of metabolic homeostasis and its disruption during obesity promotes meta-inflammation and insulin resistance. Infection with the helminth parasite Schistosoma mansoni and treatment with its soluble egg antigens (SEA) induce a type 2 immune response in metabolic organs and improve insulin sensitivity and glucose tolerance in obese mice, yet, a causal relationship remains unproven. Here, we investigated the effects and underlying mechanisms of the T2 ribonuclease omega-1 (ω1), one of the major S mansoni immunomodulatory glycoproteins, on metabolic homeostasis. We show that treatment of obese mice with plant-produced recombinant ω1, harboring similar glycan motifs as present on the native molecule, decreased body fat mass, and improved systemic insulin sensitivity and glucose tolerance in a time- and dose-dependent manner. This effect was associated with an increase in white adipose tissue (WAT) type 2 T helper cells, eosinophils, and alternatively activated macrophages, without affecting type 2 innate lymphoid cells. In contrast to SEA, the metabolic effects of ω1 were still observed in obese STAT6-deficient mice with impaired type 2 immunity, indicating that its metabolic effects are independent of the type 2 immune response. Instead, we found that ω1 inhibited food intake, without affecting locomotor activity, WAT thermogenic capacity or whole-body energy expenditure, an effect also occurring in leptin receptor-deficient obese and hyperphagic db/db mice. Altogether, we demonstrate that while the helminth glycoprotein ω1 can induce type 2 immunity, it improves whole-body metabolic homeostasis in obese mice by inhibiting food intake via a STAT6-independent mechanism.


Asunto(s)
Ingestión de Alimentos , Endorribonucleasas/uso terapéutico , Glicoproteínas/uso terapéutico , Proteínas del Helminto/uso terapéutico , Obesidad/tratamiento farmacológico , Tejido Adiposo/efectos de los fármacos , Tejido Adiposo/metabolismo , Animales , Células Cultivadas , Endorribonucleasas/farmacología , Glicoproteínas/farmacología , Proteínas del Helminto/farmacología , Locomoción , Macrófagos/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Proteínas Recombinantes/farmacología , Proteínas Recombinantes/uso terapéutico , Schistosoma mansoni/enzimología , Linfocitos T Colaboradores-Inductores/efectos de los fármacos , Termogénesis , Nicotiana/genética , Nicotiana/metabolismo
17.
J Stroke Cerebrovasc Dis ; 31(2): 106232, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34875539

RESUMEN

BACKGROUND AND OBJECTIVES: Young adult patients may suffer from poststroke depression (PSD) and anxiety. Few studies have evaluated these important psychiatric conditions that may lead to adverse outcomes in young adults. We aimed to determine the prevalence of PSD and anxiety as well as to identify their predictors in a population of young Filipino adults (18-49 years old). METHODS: We performed a cross-sectional epidemiologic study in the largest tertiary hospital in the Philippines. The study involved the administration of a structured survey tool and review of medical records. The Hospital Anxiety and Depression Score - Pilipino version (HADS-P) was used to screen for anxiety and depression. Multivariable logistic regression analysis was performed to determine significant socio-economic and clinical risk factors of PSD and anxiety. RESULTS: 114 young adult stroke patients were included. The prevalence of depression was 20.2% while that of anxiety was 34.2%. Significant predictors of PSD were the presence of anxiety (OR 1.84; CI 1.05-3.22), lower mRS scores (mRS 3-5 OR 5.52; 95% CI 1.09-8.03) and diabetes (OR 2.09; 95% CI 1.67-6.26). Meanwhile, significant predictors of poststroke anxiety included depression (OR 7.5; 95% CI 5.02-21.94) and dependency (Barthel Index scores 95-100; OR 0.94; 95% CI 0.89-0.99). Relationship status, educational attainment, stroke subtype and location were not found to be significant predictors of PSD and anxiety. CONCLUSION: A significant proportion of young adults suffered from depression and anxiety after stroke. Clinicians should be aware of these psychiatric conditions that influence outcomes and quality of life of young adults with stroke.


Asunto(s)
Ansiedad , Depresión , Accidente Cerebrovascular , Adolescente , Adulto , Ansiedad/epidemiología , Estudios Transversales , Depresión/epidemiología , Humanos , Persona de Mediana Edad , Filipinas/epidemiología , Accidente Cerebrovascular/complicaciones , Adulto Joven
18.
Molecules ; 27(3)2022 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-35164313

RESUMEN

The ditopic halogen-bond (X-bond) donors 1,2-, 1,3-, and 1,4-diiodotetrafluorobenzene (1,2-, 1,3-, and 1,4-di-I-tFb, respectively) form binary cocrystals with the unsymmetrical ditopic X-bond acceptor trans-1-(2-pyridyl)-2-(4-pyridyl)ethylene (2,4-bpe). The components of each cocrystal (1,2-di-I-tFb)·(2,4-bpe), (1,3-di-I-tFb)·(2,4-bpe), and (1,4-di-I-tFb)·(2,4-bpe) assemble via N···I X-bonds. For (1,2-di-I-tFb)·(2,4-bpe) and (1,3-di-I-tFb)·(2,4-bpe), the X-bond donor supports the C=C bonds of 2,4-bpe to undergo a topochemical [2+2] photodimerization in the solid state: UV-irradiation of each solid resulted in stereospecific, regiospecific, and quantitative photodimerization of 2,4-bpe to the corresponding head-to-tail (ht) or head-to-head (hh) cyclobutane photoproduct, respectively.

19.
J Am Chem Soc ; 143(36): 14780-14794, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34469138

RESUMEN

Experimental and theoretical studies are reported of the first two-coordinated Si0-isocyanide compound (SIDipp)Si═C═N-ArMes (1: SIDipp (NHC) = C[N(Dipp)CH2]2, ArMes = 2,6-dimesitylphenyl), supported by an N-heterocyclic carbene (NHC). A Si atom economic two-step synthesis of 1 involves a 2e reduction of the isocyanide-stabilized silyliumylidene salt [SiBr(CNArMes)(SIDipp)][B(ArF)4] (2[B(ArF)4], ArF = B(C6H3-3,5-(CF3)2)4) with KC8. 2[B(ArF)4] was obtained from SiBr2(SIDipp) after bromide abstraction with an equimolar mixture of Na[B(ArF)4] and ArMesNC. Exact adherence to the stoichiometry is crucial in the latter reaction, since 2[B(ArF)4] reacts with SiBr2(SIDipp) via isocyanide exchange to afford the disilicon(II) salt [Si2Br3(SIDipp)2)][B(ArF)4] (3[B(ArF)4]), the reaction leading to an equilibrium that favors 3[B(ArF)4] (Keq(298 K) = 10.6, ΔH° = -10.6 kJ mol-1; ΔS° = -16.0 J mol-1 K-1). 3[B(ArF)4] was obtained selectively from the 2:1 reaction of SiBr2(SIDipp) with Na[B(ArF)4] and fully characterized. Detailed studies of 1 reveal an intriguing structure featuring a planar CNHC-Si-C-N skeleton with a V-shaped geometry at the dicoordinated Si0 center, a slightly bent Si═C═N core, a CNHC-Si-CCNR 3c-2e out of plane π-bond (HOMO), and an anticlinal conformation of the SIDipp and ArMes substituents leading to axial chirality and the presence of two enantiomers, (Ra)-1 and (Sa)-1. Compound 1 displays structural dynamics in solution, rapidly interconverting the enantiomers. The silacumulene 1 is a potent Si(SIDipp) transfer agent as demonstrated by the synthesis and full characterization of the NHC-supported germasilyne (Z)-(SIDipp)(Cl)Si═GeArMes (4) from 1 and Ge(ArMes)Cl.

20.
PLoS Biol ; 16(4): e2005504, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29668708

RESUMEN

The molecular mechanisms through which dendritic cells (DCs) prime T helper 2 (Th2) responses, including those elicited by parasitic helminths, remain incompletely understood. Here, we report that soluble egg antigen (SEA) from Schistosoma mansoni, which is well known to drive potent Th2 responses, triggers DCs to produce prostaglandin E2 (PGE2), which subsequently-in an autocrine manner-induces OX40 ligand (OX40L) expression to license these DCs to drive Th2 responses. Mechanistically, SEA was found to promote PGE2 synthesis through Dectin-1 and Dectin-2, and via a downstream signaling cascade involving spleen tyrosine kinase (Syk), extracellular signal-regulated kinase (ERK), cytosolic phospholipase A2 (cPLA2), and cyclooxygenase 1 and 2 (COX-1 and COX-2). In addition, this pathway was activated independently of the actions of omega-1 (ω-1), a previously described Th2-priming glycoprotein present in SEA. These findings were supported by in vivo murine data showing that ω-1-independent Th2 priming by SEA was mediated by Dectin-2 and Syk signaling in DCs. Finally, we found that Dectin-2-/-, and to a lesser extent Dectin-1-/- mice, displayed impaired Th2 responses and reduced egg-driven granuloma formation following S. mansoni infection, highlighting the physiological importance of this pathway in Th2 polarization during a helminth infection. In summary, we identified a novel pathway in DCs involving Dectin-1/2-Syk-PGE2-OX40L through which Th2 immune responses are induced.


Asunto(s)
Células Dendríticas/inmunología , Dinoprostona/inmunología , Lectinas Tipo C/inmunología , Schistosoma mansoni/inmunología , Esquistosomiasis mansoni/inmunología , Células Th2/inmunología , Animales , Antígenos Helmínticos/inmunología , Antígenos Helmínticos/farmacología , Comunicación Autocrina , Diferenciación Celular , Ciclooxigenasa 1/genética , Ciclooxigenasa 1/inmunología , Ciclooxigenasa 2/genética , Ciclooxigenasa 2/inmunología , Células Dendríticas/efectos de los fármacos , Células Dendríticas/parasitología , Dinoprostona/metabolismo , Enterotoxinas/farmacología , Regulación de la Expresión Génica , Humanos , Lectinas Tipo C/deficiencia , Lectinas Tipo C/genética , Sistema de Señalización de MAP Quinasas , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/inmunología , Proteínas de la Membrana/genética , Proteínas de la Membrana/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ligando OX40 , Fosfolipasas A2/genética , Fosfolipasas A2/inmunología , Cultivo Primario de Células , Especies Reactivas de Oxígeno/inmunología , Especies Reactivas de Oxígeno/metabolismo , Esquistosomiasis mansoni/genética , Esquistosomiasis mansoni/parasitología , Esquistosomiasis mansoni/patología , Quinasa Syk/genética , Quinasa Syk/inmunología , Células Th2/efectos de los fármacos , Células Th2/parasitología , Factores de Necrosis Tumoral/genética , Factores de Necrosis Tumoral/inmunología
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