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1.
J Chem Phys ; 160(5)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38299630

RESUMO

We describe Reflection Absorption Infrared Spectroscopy (RAIRS) and first-principles Density Functional Theory (DFT) studies of ammonia adsorption on the Cu{311} surface. Our experimental results indicate an upright chemisorbed species at low coverages, with at least one additional species accompanying this at higher coverages. Our high-coverage RAIRS data cannot be fully explained by DFT models containing only ammonia or its dissociation products, even allowing for molecular tilt and/or the formation of a bilayer. We therefore also consider urea and formamide as possible products of surface reaction with residual carbon monoxide, but these species are again not fully compatible with our observed spectra. The overlayer composition at high coverages remains mysterious.

3.
Cancers (Basel) ; 15(13)2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-37444449

RESUMO

Multiple myeloma (MM) patients risk diagnostic delays and irreversible organ damage. In those with newly diagnosed myeloma, we explored the presenting symptoms to identify early signals of MM and their relationships to organ damage. The symptoms were recorded in patients' own words at diagnosis and included diagnostic time intervals. Those seen by a haematologist >6 months prior to MM diagnosis were classified as precursor disease (PD). Most (962/977) patients provided data. Back pain (38%), other pain (31%) and systemic symptoms (28%) predominated. Patients rarely complain of 'bone pain', simply 'pain'. Vertebral fractures are under-recognised as pathological and are the predominant irreversible organ damage (27% of patients), impacting the performance status (PS) and associated with back pain (odds ratio (OR) 6.14 [CI 4.47-8.44]), bone disease (OR 3.71 [CI 1.88-7.32]) and age >65 years (OR 1.58 [CI 1.15-2.17]). Renal failure is less frequent and associated with gastrointestinal symptoms (OR 2.23 [CI1.28-3.91]), age >65 years (OR 2.14 [CI1.28-3.91]) and absence of back pain (OR 0.44 [CI 0.29-0.67]). Patients with known PD (n = 149) had fewer vertebral fractures (p = 0.001), fewer adverse features (p = 0.001), less decline in PS (p = 0.001) and a lower stage (p = 0.04) than 813 with de novo MM. Our data suggest subgroups suitable for trials of 'symptom-directed' screening: those with back pain, unexplained pain, a general decline in health or low-impact vertebral compression fractures.

4.
Infect Immun ; 91(6): e0003123, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37162364

RESUMO

Cystic echinococcosis is caused by the larval stages (hydatids) of cestode parasites belonging to the species cluster Echinococcus granulosus sensu lato, with E. granulosus sensu stricto being the main infecting species. Hydatids are bladderlike structures that attain large sizes within various internal organs of livestock ungulates and humans. Hydatids are protected by the massive acellular laminated layer (LL), composed mainly of mucins. Parasite growth requires LL turnover, and abundant LL-derived particles are found at infection sites in infected humans, raising the question of how LL materials are dealt with by the hosts. In this article, we show that E. granulosus sensu stricto LL mucins injected into mice are taken up by Kupffer cells, the liver macrophages exposed to the vascular space. This uptake is largely dependent on the intact mucin glycans and on Clec4F, a C-type lectin receptor which, in rodents, is selectively expressed in Kupffer cells. This uptake mechanism operates on mucins injected both in soluble form intravenously (i.v.) and in particulate form intraperitoneally (i.p.). In mice harboring intraperitoneal infections by the same species, LL mucins were found essentially only at the infection site and in the liver, where they were taken up by Kupffer cells via Clec4F. Therefore, shed LL materials circulate in the host, and Kupffer cells can act as a sink for these materials, even when the parasite grows in sites other than the liver.


Assuntos
Equinococose , Echinococcus granulosus , Animais , Humanos , Camundongos , Equinococose/parasitologia , Echinococcus granulosus/química , Genótipo , Células de Kupffer , Lectinas , Mucinas
5.
Nature ; 616(7957): 443-447, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36858073

RESUMO

Although no known asteroid poses a threat to Earth for at least the next century, the catalogue of near-Earth asteroids is incomplete for objects whose impacts would produce regional devastation1,2. Several approaches have been proposed to potentially prevent an asteroid impact with Earth by deflecting or disrupting an asteroid1-3. A test of kinetic impact technology was identified as the highest-priority space mission related to asteroid mitigation1. NASA's Double Asteroid Redirection Test (DART) mission is a full-scale test of kinetic impact technology. The mission's target asteroid was Dimorphos, the secondary member of the S-type binary near-Earth asteroid (65803) Didymos. This binary asteroid system was chosen to enable ground-based telescopes to quantify the asteroid deflection caused by the impact of the DART spacecraft4. Although past missions have utilized impactors to investigate the properties of small bodies5,6, those earlier missions were not intended to deflect their targets and did not achieve measurable deflections. Here we report the DART spacecraft's autonomous kinetic impact into Dimorphos and reconstruct the impact event, including the timeline leading to impact, the location and nature of the DART impact site, and the size and shape of Dimorphos. The successful impact of the DART spacecraft with Dimorphos and the resulting change in the orbit of Dimorphos7 demonstrates that kinetic impactor technology is a viable technique to potentially defend Earth if necessary.

6.
Protein Cell ; 14(2): 87-104, 2023 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-36929004

RESUMO

The larval stages of the cestode parasites belonging to the genus Echinococcus grow within internal organs of humans and a range of animal species. The resulting diseases, collectively termed echinococcoses, include major neglected tropical diseases of humans and livestock. Echinococcus larvae are outwardly protected by the laminated layer (LL), an acellular structure that is unique to this genus. The LL is based on a fibrillar meshwork made up of mucins, which are decorated by galactose-rich O-glycans. In addition, in the species cluster termed E. granulosus sensu lato, the LL features nano-deposits of the calcium salt of myo-inositol hexakisphosphate (Insp6). The main purpose of our article is to update the immunobiology of the LL. Major recent advances in this area are (i) the demonstration of LL "debris" at the infection site and draining lymph nodes, (ii) the characterization of the decoy activity of calcium Insp6 with respect to complement, (iii) the evidence that the LL mucin carbohydrates interact specifically with a lectin receptor expressed in Kupffer cells (Clec4F), and (iv) the characterization of what appear to be receptor-independent effects of LL particles on dendritic cells and macrophages. Much information is missing on the immunology of this intriguing structure: we discuss gaps in knowledge and propose possible avenues for research.


Assuntos
Equinococose , Echinococcus granulosus , Echinococcus , Animais , Cálcio , Equinococose/parasitologia , Echinococcus/imunologia , Echinococcus granulosus/química , Echinococcus granulosus/imunologia , Mucinas
7.
Br J Haematol ; 201(4): 682-689, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36822820

RESUMO

Daratumumab, bortezomib and dexamethasone (DVd) is approved for patients with relapsed multiple myeloma following the CASTOR phase 3 clinical trial. This retrospective multicentre analysis assesses the overall response rate (ORR) and progression-free survival (PFS) in routine clinical practice for patients at first relapse treated with DVd incorporating weekly bortezomib. Data were collected from 296 sequential patients treated across 15 UK centres. After a median follow-up of 21 months, the ORR was 82% (26% partial response, 56% very good partial response or better) and the median PFS was 16 months [95% confidence interval (CI) 12-20 months]. Results were similar regardless of prior lenalidomide exposure. The median time to next treatment was 20 months (95% CI 15-25 months) and the estimated overall survival at two years was 74%. Patients with high-risk features (by cytogenetics, International Staging System or extramedullary disease) and those treated within 18 months of initiation of progression-free treatment, or within 12 months of autologous stem cell transplant, had significantly inferior outcomes. The grade 2 and 3 peripheral neuropathy rate was 7%. DVd with weekly bortezomib was effective in a heterogenous real-world population at first relapse with a low rate of peripheral neuropathy. However, high-risk patients had inferior outcomes and should be considered for alternative treatments.


Assuntos
Mieloma Múltiplo , Humanos , Bortezomib/uso terapêutico , Estudos Retrospectivos , Dexametasona/efeitos adversos , Doença Crônica , Recidiva , Reino Unido/epidemiologia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
8.
J Phys Chem C Nanomater Interfaces ; 127(1): 229-233, 2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36660097

RESUMO

Adsorption of chiral molecules on chiral surfaces implies diastereomerism, evident in the adoption of distinct adsorption geometries. We show here that this diastereomerism produces a signature in the motion of chiral molecules desorbing from a chiral surface. The rotations of S- and R-alanine molecules are analyzed upon desorption from R-Cu{531} using first-principles molecular dynamics simulations. S-Ala molecules exhibit a larger angular momentum, with a clear preference for one rotational sense, whereas no such preference is observed for R-Ala molecules upon desorption from this surface. These trends would be reversed for desorption from the S-Cu{531} surface. Possible applications include chiral separation techniques and enantiospecific sensors.

10.
Langmuir ; 38(23): 7256-7271, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35649267

RESUMO

The interaction of highly reactive species with solid surfaces can result in modes of adsorption quite distinct from the classic molecular and dissociative events that are usually thought to dominate. For instance, compelling experimental evidence suggests that adsorption of F2 at the Si{001} surface is often initiated by abstraction (and binding at the surface) of just one fluorine atom from the molecule; the second fluorine atom subsequently experiences either a separate atomic adsorption event or ejection from the surface altogether. Molecular dynamics simulations using empirical potentials support this concept but massively overestimate the prevalence of atomic ejection. In this work, we report first-principles molecular dynamics calculations that correctly show atomic ejection to be rare while providing insight into the details of abstractive adsorption. In addition, we also examine the case of F2 adsorption onto a monohydrogenated Si{001} surface, finding evidence for a different type of abstractive adsorption, in which a hydrogen atom may be removed from the surface to form a short-lived HFF intermediate. The latter rapidly decomposes to produce either HF or (via reaction with another surface hydrogen atom) H2.

11.
Eur J Immunol ; 52(8): 1243-1257, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35568024

RESUMO

The murine serous cavities contain a rare and enigmatic population of short-lived F4/80lo MHCII+ macrophages but what regulates their development, survival, and fate is unclear. Here, we show that mature F4/80lo MHCII+ peritoneal macrophages arise after birth, but that this occurs largely independently of colonization by microbiota. Rather, microbiota specifically regulate development of a subpopulation of CD11c+ cells that express the immunoregulatory cytokine RELM-α, are reliant on the transcription factor EGR2, and develop independently of the growth factor CSF1. Furthermore, we demonstrate that intrinsic expression of RELM-α, a signature marker shared by CD11c+ and CD11c- F4/80lo MHCII+ cavity macrophages, regulates survival and differentiation of these cells in the peritoneal cavity in a sex-specific manner. Thus, we identify a previously unappreciated diversity in serous cavity F4/80lo MHCII+ macrophages that is regulated by microbiota, and describe a novel sex and site-specific function for RELM-α in regulating macrophage endurance that reveals the unique survival challenge presented to monocyte-derived macrophages by the female peritoneal environment.


Assuntos
Antígeno CD11c , Proteína 2 de Resposta de Crescimento Precoce , Macrófagos Peritoneais , Microbiota , Animais , Antígeno CD11c/metabolismo , Diferenciação Celular , Proteína 2 de Resposta de Crescimento Precoce/metabolismo , Feminino , Macrófagos Peritoneais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Caracteres Sexuais
12.
Clin Infect Dis ; 75(12): 2066-2075, 2022 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-35522019

RESUMO

BACKGROUND: Patients with bacteremia due to carbapenem-resistant Enterobacterales (CRE) experience delays until appropriate therapy and high mortality rates. Rapid molecular diagnostics for carbapenemases and new ß-lactam/ß-lactamase inhibitors may improve outcomes. METHODS: We conducted an observational study of patients with CRE bacteremia from 2016 to 2018 at 8 New York and New Jersey medical centers and assessed center-specific clinical microbiology practices. We compared time to receipt of active antimicrobial therapy and mortality between patients whose positive blood cultures underwent rapid molecular testing for the Klebsiella pneumoniae carbapenemase (KPC) gene (blaKPC) and patients whose cultures did not undergo this test. CRE isolates underwent antimicrobial susceptibility testing by broth microdilution and carbapenemase profiling by whole-genome sequencing. We also assessed outcomes when ceftazidime-avibactam and polymyxins were used as targeted therapies. RESULTS: Of 137 patients with CRE bacteremia, 89 (65%) had a KPC-producing organism. Patients whose blood cultures underwent blaKPC PCR testing (n = 51) had shorter time until receipt of active therapy (median: 24 vs 50 hours; P = .009) compared with other patients (n = 86) and decreased 14-day (16% vs 37%; P = .007) and 30-day (24% vs 47%; P = .007) mortality. blaKPC PCR testing was associated with decreased 30-day mortality (adjusted odds ratio: .37; 95% CI: .16-.84) in an adjusted model. The 30-day mortality rate was 10% with ceftazidime-avibactam monotherapy and 31% with polymyxin monotherapy (P = .08). CONCLUSIONS: In a KPC-endemic area, blaKPC PCR testing of positive blood cultures was associated with decreased time until appropriate therapy and decreased mortality for CRE bacteremia, and ceftazidime-avibactam is a reasonable first-line therapy for these infections.


Assuntos
Bacteriemia , Infecções por Klebsiella , Humanos , Klebsiella pneumoniae , Antibacterianos/uso terapêutico , Carbapenêmicos/farmacologia , Infecções por Klebsiella/tratamento farmacológico , Ceftazidima/uso terapêutico , beta-Lactamases/genética , Proteínas de Bactérias/genética , Compostos Azabicíclicos/uso terapêutico , Combinação de Medicamentos , Inibidores de beta-Lactamases/uso terapêutico , Bacteriemia/tratamento farmacológico , Testes de Sensibilidade Microbiana
13.
Nat Immunol ; 23(6): 927-939, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35624205

RESUMO

Hypoxemia is a defining feature of acute respiratory distress syndrome (ARDS), an often-fatal complication of pulmonary or systemic inflammation, yet the resulting tissue hypoxia, and its impact on immune responses, is often neglected. In the present study, we have shown that ARDS patients were hypoxemic and monocytopenic within the first 48 h of ventilation. Monocytopenia was also observed in mouse models of hypoxic acute lung injury, in which hypoxemia drove the suppression of type I interferon signaling in the bone marrow. This impaired monopoiesis resulted in reduced accumulation of monocyte-derived macrophages and enhanced neutrophil-mediated inflammation in the lung. Administration of colony-stimulating factor 1 in mice with hypoxic lung injury rescued the monocytopenia, altered the phenotype of circulating monocytes, increased monocyte-derived macrophages in the lung and limited injury. Thus, tissue hypoxia altered the dynamics of the immune response to the detriment of the host and interventions to address the aberrant response offer new therapeutic strategies for ARDS.


Assuntos
Lesão Pulmonar , Síndrome do Desconforto Respiratório , Animais , Humanos , Hipóxia/etiologia , Inflamação/complicações , Pulmão , Lesão Pulmonar/complicações , Camundongos
14.
Immunology ; 166(4): 458-474, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35437746

RESUMO

The relationship between macrophages of the peritoneal cavity and the adjacent omentum remains poorly understood. Here, we describe two populations of omental macrophages distinguished by CD102 expression and use an adoptive cell transfer approach to investigate whether these arise from peritoneal macrophages, and whether this depends upon inflammatory status, the origin of peritoneal macrophages and availability of the omental niches. We show that whereas established resident peritoneal macrophages largely fail to migrate to the omentum, monocyte-derived resident cells readily migrate and form a substantial component of omental CD102+ macrophages in the months following resolution of peritoneal inflammation. In contrast, both populations had the capacity to migrate to the omentum in the absence of endogenous peritoneal and omental macrophages. However, inflammatory macrophages expanded more effectively and more efficiently repopulated both CD102+ and CD102- omental populations, whereas established resident macrophages partially reconstituted the omental niche via recruitment of monocytes. Hence, cell origin determines the migration of peritoneal macrophages to the omentum and predisposes established resident macrophages to drive infiltration of monocyte-derived cells.


Assuntos
Macrófagos Peritoneais , Omento , Macrófagos , Omento/metabolismo , Cavidade Peritoneal
15.
J Econ Inequal ; 20(1): 151-168, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35382353

RESUMO

UK official statistics on income distribution have incorporated top-income adjustments to household survey data since 1992. This article reviews the work undertaken by the Department for Work and Pensions and the Office for National Statistics, and the academic research that influenced them, and reflects on the lessons to learn from the UK experience.

16.
J Colloid Interface Sci ; 619: 377-387, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35398768

RESUMO

The dehydrogenation of alkane feedstock to produce alkenes is a significant and energy intensive industrial process, generally occurring on metals and metal oxides. Here, we investigate a catalytic mechanism for the dehydrogenation of butane on single-layer, metal-free graphene using a combination of ab initio quantum chemical calculations and adsorption microcalorimetry. Dispersion-corrected Density Functional Theory (DFT) is employed to calculate transition states and energy minima that describe the reaction pathways connecting butane to the two possible products, but-1-ene and but-2-ene. The deprotonations occur with moderate energy barriers in the 0.54 eV-0.69 eV range. A strong agreement is observed between the results of the adsorption energies calculated by DFT (0.40 eV) and the measured differential heat of adsorption of n-butane on a graphitic overlayer. We conclude that the active-site for this catalytic reaction is a metal-free graphene vacancy, created by removing a carbon atom from a single-layer graphene sheet.

17.
Cancers (Basel) ; 14(3)2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-35159100

RESUMO

There is a growing body of evidence that cancer causes systemic changes. These influences are most evident in the bone marrow and the blood, particularly in the myeloid compartment. Here, we show that there is an increase in the number of bone marrow, circulating and splenic monocytes by using mouse models of breast cancer caused by the mammary epithelial expression of the polyoma middle T antigen. Cancer does not affect ratios of classical to non-classical populations of monocytes in the circulation nor does it affect their half-lives. Single cell RNA sequencing also indicates that cancer does not induce any new monocyte populations. Cancer does not change the monocytic progenitor number in the bone marrow, but the proliferation rate of monocytes is higher, thus providing an explanation for the expansion of the circulating numbers. Deep RNA sequencing of these monocytic populations reveals that cancer causes changes in the classical monocyte compartment, with changes evident in bone marrow monocytes and even more so in the blood, suggesting influences in both compartments, with the down-regulation of interferon type 1 signaling and antigen presentation being the most prominent of these. Consistent with this analysis, down-regulated genes are enriched with STAT1/STAT2 binding sites in their promoter, which are transcription factors required for type 1 interferon signaling. However, these transcriptome changes in mice did not replicate those found in patients with breast cancer. Consequently, this mouse model of breast cancer may be insufficient to study the systemic influences of human cancer.

19.
Infect Control Hosp Epidemiol ; 43(1): 92-95, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33583476

RESUMO

A retrospective study was conducted to describe the impact of a molecular assay to detect the most common carbapenemase genes in carbapenem-resistant Enterobacterales isolates recovered in culture. Carbapenemases were detected in 69% of isolates, and assay results guided treatment modifications or epidemiologic investigation in 20% and 4% of cases, respectively.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos , Carbapenêmicos , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Carbapenêmicos/farmacologia , Humanos , Estudos Retrospectivos , beta-Lactamases/genética
20.
Mol Phys ; 119(15-16): e1900940, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34848893

RESUMO

Using a combination of X-ray diffraction and simulation techniques, we are able to identify a crystalline monolayer of 1,3,5-triiodotrifluorobenzene formed on graphite. The monolayer is found to exhibit an incommensurate hexagonal unit cell with a lattice parameter of 9.28(7) Å, exhibiting a trigonal arrangement of iodine atoms not found in the bulk structure. DFT simulations have been performed exhibiting close agreement with the experimental structure. Importantly these simulations can be used to compare the strength of the intermolecular interactions both with and without Van der Waals corrections. Thus it is possible to estimate that halogen bonding consists of approximately half the total interaction energy. This demonstrates that despite the presence of strong directional non-covalent bonding, dispersion interactions account for a very significant proportion of the total energy.

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