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1.
Phys Chem Chem Phys ; 26(14): 10784-10795, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38516916

RESUMO

Photodouble ionization (PDI) triple-differential cross sections (TDCSs) of benzene and thiophene have been measured in electron-electron coincidence experiments under 10-10 eV and 20-20 eV equal energy sharing conditions. A multi-Gaussian fit method has been employed to characterize the TDCSs. The trends and features observed for benzene and thiophene do highlight differences with helium most likely from molecular PDI contributions to the TDCS. A comparison with the well-known helium PDI TDCS for equal energy sharing conditions [Avaldi and Huetz J. Phys. B: At. Mol. Opt. Phys., 2005, 38, S861-S891] supported the validity of the multi-Gaussian fitting method and contextualized the benzene and thiophene fits. The molecular targets and energy sharing conditions were chosen to provide insight into the unexpected resonances observed in aromatic hydrocarbons but not aromatic heterocyclic molecules [Wehlitz et al., Phys. Rev. Lett., 2012, 109, 193001]. Contrary to the work of [Wehlitz et al., Phys. Rev. Lett., 2012, 109, 193001], no significant differences between benzene and thiophene were found.

2.
Blood ; 136(8): 957-973, 2020 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-32369597

RESUMO

Modulators of epithelial-to-mesenchymal transition (EMT) have recently emerged as novel players in the field of leukemia biology. The mechanisms by which EMT modulators contribute to leukemia pathogenesis, however, remain to be elucidated. Here we show that overexpression of SNAI1, a key modulator of EMT, is a pathologically relevant event in human acute myeloid leukemia (AML) that contributes to impaired differentiation, enhanced self-renewal, and proliferation of immature myeloid cells. We demonstrate that ectopic expression of Snai1 in hematopoietic cells predisposes mice to AML development. This effect is mediated by interaction with the histone demethylase KDM1A/LSD1. Our data shed new light on the role of SNAI1 in leukemia development and identify a novel mechanism of LSD1 corruption in cancer. This is particularly pertinent given the current interest surrounding the use of LSD1 inhibitors in the treatment of multiple different malignancies, including AML.


Assuntos
Transformação Celular Neoplásica , Transição Epitelial-Mesenquimal/genética , Histona Desmetilases/metabolismo , Leucemia Mieloide Aguda/patologia , Fatores de Transcrição da Família Snail/fisiologia , Animais , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Células HEK293 , Células HL-60 , Histona Desmetilases/genética , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Camundongos , Camundongos Transgênicos , Ligação Proteica , Fatores de Transcrição da Família Snail/genética , Fatores de Transcrição da Família Snail/metabolismo
3.
Tob Control ; 31(Suppl 3): s187-s196, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36328463

RESUMO

INTRODUCTION: Local e-cigarette sales restrictions (ESRs) may impact e-cigarette use. This study examined the associations between living in localities with various ESR policies and changes in e-cigarette use among young adults in Los Angeles (LA) County, California, USA. METHODS: Data were from a cohort of LA County young adults (18-21 years; n=2100) who completed two waves of surveys (Fall 2018-Summer 2019 and Summer-Fall 2020). Local flavoured (n=9) and comprehensive (n=2) ESRs in LA County implemented between June 2019 and May 2020 were identified, coded and merged with the baseline data. Multivariable logistic regressions were used to examine the associations between living in ESR localities and e-cigarette use at follow-up, controlling for covariates and stratified by cigarette smoking at baseline. RESULTS: Overall, 20.9% and 14.3% of participants lived in localities with flavoured and comprehensive ESRs, respectively. Participants who were non-Hispanic, had higher socioeconomic statuses and were currently using e-cigarettes were generally more likely to live in ESR localities than their counterparts. The associations between living in ESR localities and e-cigarette use at follow-up were not found among baseline non-e-cigarette users regardless of their cigarette smoking status; a positive relationship was found among baseline e-cigarette users who also smoked cigarettes but not among non-smokers. DISCUSSION: Participants who lived in localities with various ESR policies were different in their baseline e-cigarette use and socioeconomic backgrounds. Future research examining the potential impact of ESRs on e-cigarette use change should consider the localities' overall sociodemographic and tobacco-using characteristics and individuals' cigarette smoking histories.


Assuntos
Fumar Cigarros , Sistemas Eletrônicos de Liberação de Nicotina , Produtos do Tabaco , Vaping , Adulto Jovem , Humanos , Los Angeles/epidemiologia , Vaping/epidemiologia , Aromatizantes
4.
J Allergy Clin Immunol ; 147(3): 1049-1062.e7, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32679208

RESUMO

BACKGROUND: Allergic skin inflammation often presents in early childhood; however, little is known about the events leading to its initiation and whether it is transient or long-term in nature. OBJECTIVE: We sought to determine the immunologic rules that govern skin inflammation in early life. METHODS: Neonatal and adult mice were epicutaneously sensitized with allergen followed by airway allergen challenge. Epicutaneous application of labeled allergen allowed for determination of antigen uptake and processing by antigen-presenting cells. RNAseq and microbiome analysis was performed on skin from neonatal and adult specific pathogen-free and germ-free mice. RESULTS: A mixed TH2/TH17 inflammatory response in the skin and the lungs of adult mice was observed following sensitization and challenge. Comparatively, neonatal mice did not develop overt skin inflammation, but exhibited systemic release of IL-17a and a TH2-dominated lung response. Mechanical skin barrier disruption was not sufficient to drive allergic skin inflammation, although it did promote systemic immune priming. Skin of neonatal mice and adult germ-free mice was seeded with low numbers of antigen-presenting cells and impaired chemokine and alarmin production. Enhanced chemokine and alarmin production, and seeding of the skin with antigen-presenting cells capable of instructing recruited cells to elicit their effector function, was, at least in part, dependent on formation of the microbiome, and consequently contributed to the development of overt skin disease. CONCLUSIONS: These data shed light on the principles that underlie allergic inflammation in different tissues and highlight a window of opportunity that might exist for early-life prevention of allergic diseases.


Assuntos
Células Apresentadoras de Antígenos/imunologia , Hipersensibilidade/imunologia , Inflamação/imunologia , Pulmão/imunologia , Microbiota/imunologia , Pele/imunologia , Células Th2/imunologia , Animais , Antígenos de Dermatophagoides/imunologia , Movimento Celular , Quimiocinas/metabolismo , Modelos Animais de Doenças , Feminino , Vida Livre de Germes , Humanos , Hipersensibilidade/microbiologia , Inflamação/microbiologia , Interleucina-17/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pyroglyphidae
5.
J Ethn Subst Abuse ; : 1-19, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35943488

RESUMO

This study assessed the hypothetical impact of flavored cigar sales restrictions on cigar smoking among Black young adult cigar smokers (ages 21-29). Forty in-depth interviews were conducted in 2020. Interviews were independently coded and analyzed using thematic analysis. When asked how they would smoke cigars given a flavor sales restriction, half of participants reported they would smoke in the same way, a third would stop or reduce smoking, and a few were unsure of what they would do. Cigar smoking outcome expectancies, preference for flavors, and perceived addictiveness of cigar products may predict cigar smoking change given flavor sales restrictions.

6.
Am J Physiol Renal Physiol ; 320(3): F442-F453, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33459165

RESUMO

Diabetic nephropathy (DN) is the leading cause of end-stage kidney disease. Besides glycemic and blood pressure control, environmental factors such as cigarette smoking (CS) adversely affect the progression of DN. The effects of CS on DN progression have been attributed to combustion-generated molecules without consideration to the role of nicotine (NIC), responsible for the addictive properties of both CS and electronic cigarettes (ECs). Podocytes are essential to preserve the structure and function of the glomerular filtration barrier, and strong evidence indicates that early podocyte loss promotes DN progression. We performed experiments in human podocytes and in a mouse model of diabetes that develops nephropathy resembling human DN. We determined that NIC binding to podocytes in concentrations achieved with CS and ECs activated NADPH oxidase, which sets in motion a dysfunctional molecular network integrated by cyclooxygenase 2, known to induce podocyte injury; downregulation of AMP-activated protein kinase, important for maintaining cellular energy stores and antioxidation; and upregulation of CD36, which increased lipid uptake and promoted apoptosis. In diabetic mice, NIC increased proteinuria, a recognized marker of chronic kidney disease progression, accompanied by reduced glomerular podocyte synaptopodin, a crucial stabilizer of the podocyte cytoskeleton, and increased fibronectin expression. This novel study critically implicates NIC itself as a contributor to DN progression in CS and EC users.NEW & NOTEWORTHY In this study, we demonstrate that nicotine increases the production of reactive oxygen species, increases cyclooxygenase-2 expression, and upregulates Cd36 while inducing downregulation of AMP-activated protein kinase. In vivo nicotine increases proteinuria and fibronectin expression in diabetic mice. This study demonstrates that effects of nicotine on podocytes are responsible, at least in part, for the deleterious effects of smoking in the progression of chronic kidney disease, including diabetic nephropathy.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Nefropatias Diabéticas/metabolismo , Nicotina/farmacologia , Podócitos/metabolismo , Fumar/efeitos adversos , Animais , Apoptose/efeitos dos fármacos , Diabetes Mellitus Experimental/metabolismo , Nefropatias Diabéticas/tratamento farmacológico , Humanos , Camundongos , Podócitos/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
7.
Emerg Infect Dis ; 27(3): 894-904, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33622474

RESUMO

Much about the range of pathogens, frequency of coinfection, and clinical effects of reproductive tract infections (RTIs) among pregnant women remains unknown. We report on RTIs (Mycoplasma genitalium, Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis, Treponema pallidum subspecies pallidum, bacterial vaginosis, and vulvovaginal candidiasis) and other reproductive health indicators in 699 pregnant women in Papua New Guinea during 2015-2017. We found M. genitalium, an emerging pathogen in Papua New Guinea, in 12.5% of participants. These infections showed no evidence of macrolide resistance. In total, 74.1% of pregnant women had >1 RTI; most of these infections were treatable. We detected sexually transmitted infections (excluding syphilis) in 37.7% of women. Our findings showed that syndromic management of infections is greatly inadequate. In total, 98.4% of women had never used barrier contraception. These findings will inform efforts to improve reproductive healthcare in Papua New Guinea.


Assuntos
Infecções por Chlamydia , Gonorreia , Infecções por Mycoplasma , Mycoplasma genitalium , Infecções do Sistema Genital , Infecções Sexualmente Transmissíveis , Antibacterianos , Chlamydia trachomatis , Farmacorresistência Bacteriana , Feminino , Humanos , Macrolídeos , Neisseria gonorrhoeae , Papua Nova Guiné , Gravidez , Gestantes
8.
Development ; 145(19)2018 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-30185409

RESUMO

Stem cell leukemia (Scl or Tal1) and lymphoblastic leukemia 1 (Lyl1) encode highly related members of the basic helix-loop-helix family of transcription factors that are co-expressed in the erythroid lineage. Previous studies have suggested that Scl is essential for primitive erythropoiesis. However, analysis of single-cell RNA-seq data of early embryos showed that primitive erythroid cells express both Scl and Lyl1 Therefore, to determine whether Lyl1 can function in primitive erythropoiesis, we crossed conditional Scl knockout mice with mice expressing a Cre recombinase under the control of the Epo receptor, active in erythroid progenitors. Embryos with 20% expression of Scl from E9.5 survived to adulthood. However, mice with reduced expression of Scl and absence of Lyl1 (double knockout; DKO) died at E10.5 because of progressive loss of erythropoiesis. Gene expression profiling of DKO yolk sacs revealed loss of Gata1 and many of the known target genes of the SCL-GATA1 complex. ChIP-seq analyses in a human erythroleukemia cell line showed that LYL1 exclusively bound a small subset of SCL targets including GATA1. Together, these data show for the first time that Lyl1 can maintain primitive erythropoiesis.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Eritropoese , Proteínas de Neoplasias/metabolismo , Animais , Sequência de Bases , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Embrião de Mamíferos/citologia , Eritrócitos/metabolismo , Células Eritroides/metabolismo , Eritropoese/genética , Fator de Transcrição GATA1/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Camundongos Knockout , Proteínas de Neoplasias/genética , Ligação Proteica , Células-Tronco/metabolismo , Proteína 1 de Leucemia Linfocítica Aguda de Células T/genética , Proteína 1 de Leucemia Linfocítica Aguda de Células T/metabolismo
9.
Eur J Nucl Med Mol Imaging ; 48(5): 1371-1389, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33179151

RESUMO

PURPOSE: The aim of the present paper is to review the role of HER2 antibodies, affibodies and nanobodies as vehicles for imaging and therapy approaches in breast cancer, including a detailed look at recent clinical data from antibody drug conjugates and nanobodies as well as affibodies that are currently under development. RESULTS: Clinical and preclinical studies have shown that the use of monoclonal antibodies in molecular imaging is impaired by slow blood clearance, associated with slow and low tumor uptake and with limited tumor penetration potential. Antibody fragments, such as nanobodies, on the other hand, can be radiolabelled with short-lived radioisotopes and provide high-contrast images within a few hours after injection, allowing early diagnosis and reduced radiation exposure of patients. Even in therapy, the small radioactively labeled nanobodies prove to be superior to radioactively labeled monoclonal antibodies due to their higher specificity and their ability to penetrate the tumor. CONCLUSION: While monoclonal antibodies are well established drug delivery vehicles, the current literature on molecular imaging supports the notion that antibody fragments, such as affibodies or nanobodies, might be superior in this approach.


Assuntos
Neoplasias da Mama , Preparações Farmacêuticas , Anticorpos de Domínio Único , Neoplasias da Mama/diagnóstico por imagem , Humanos , Radioimunodetecção , Radioimunoterapia , Receptor ErbB-2
10.
FASEB J ; 34(12): 16191-16204, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33070369

RESUMO

Urinary plasminogen/plasmin, or plasmin (ogen) uria, has been demonstrated in proteinuric patients and exposure of cultured podocytes to plasminogen results in injury via oxidative stress pathways. A causative role for plasmin (ogen) as a "second hit" in kidney disease progression has yet to have been demonstrated in vivo. Additionally, association between plasmin (ogen) uria and kidney function in glomerular diseases remains unclear. We performed comparative studies in a puromycin aminonucleoside (PAN) nephropathy rat model treated with amiloride, an inhibitor of plasminogen activation, and measured changes in plasmin (ogen) uria. In a glomerular disease biorepository cohort (n = 128), we measured time-of-biopsy albuminuria, proteinuria, and plasmin (ogen) uria for correlations with kidney outcomes. In cultured human podocytes, plasminogen treatment was associated with decreased focal adhesion marker expression with rescue by amiloride. Increased glomerular plasmin (ogen) was found in PAN rats and focal segmental glomerulosclerosis (FSGS) patients. PAN nephropathy was associated with increases in plasmin (ogen) uria and proteinuria. Amiloride was protective against PAN-induced glomerular injury, reducing CD36 scavenger receptor expression and oxidative stress. In patients, we found associations between plasmin (ogen) uria and edema status as well as eGFR. Our study demonstrates a role for plasmin (ogen)-induced podocyte injury in the PAN nephropathy model, with amiloride having podocyte-protective properties. In one of the largest glomerular disease cohorts to study plasminogen, we validated previous findings while suggesting a potentially novel relationship between plasmin (ogen) uria and estimated glomerular filtration rate (eGFR). Together, these findings suggest a role for plasmin (ogen) in mediating glomerular injury and as a viable targetable biomarker for podocyte-sparing treatments.


Assuntos
Edema/patologia , Nefropatias/patologia , Glomérulos Renais/patologia , Plasminogênio/urina , Podócitos/patologia , Proteinúria/patologia , Amilorida/farmacologia , Animais , Biomarcadores/metabolismo , Biomarcadores/urina , Edema/metabolismo , Glomerulosclerose Segmentar e Focal/metabolismo , Glomerulosclerose Segmentar e Focal/patologia , Humanos , Nefropatias/metabolismo , Glomérulos Renais/efeitos dos fármacos , Glomérulos Renais/metabolismo , Masculino , Estresse Oxidativo/efeitos dos fármacos , Podócitos/efeitos dos fármacos , Podócitos/metabolismo , Proteinúria/metabolismo , Puromicina Aminonucleosídeo/metabolismo , Ratos , Ratos Wistar , Insuficiência Renal/metabolismo , Insuficiência Renal/patologia
11.
Int J Clin Pract ; 75(3): e13725, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32965728

RESUMO

BACKGROUND: The 2019 coronavirus disease (COVID-19) has become a global pandemic and the published literature describing the virus has grown exponentially. METHODS: We conducted a systematic review of the literature to identify the symptoms, comorbidities present, radiological features and outcomes for adults testing positive for COVID-19 admitted to hospital. The results across multiple studies were numerically pooled to yield total estimated. RESULTS: A total of 45 studies were included in this review with 14 358 adult participants (average age 51 years, male 51%). The pooled findings suggest that the most common symptom among patients was fever (81.2%) followed by cough (62.9%), fatigue (38.0%) and anorexia/loss of appetite (33.7%). The comorbidities that were most prevalent among patients with the virus were hypertension (19.1%), cardiovascular disease (17.9%), endocrine disorder (9.3%) and diabetes (9.2%). Abnormal chest X-ray findings were present in 27.7% of patients and ground-glass opacity was demonstrated on chest computerized tomography in 63.0% of patients. The most frequent adverse outcomes were acute respiratory distress syndrome (27.4%), acute cardiac injury (16.2%) and acute kidney injury (12.6%). Death occurred in 8.2% of patients and 16.3% required intensive care admission and 11.7% had mechanical ventilation. Bacterial or secondary infections affected 8.5% of patients and 6.9% developed shock. CONCLUSIONS: COVID-19 most commonly presents with fever, cough, fatigue and anorexia and among patients with existing hypertension and cardiovascular disease. It is important as serious adverse outcomes can develop such as acute respiratory distress syndrome, acute cardiac injury, acute kidney injury and death.


Assuntos
COVID-19 , Adulto , Tosse/epidemiologia , Febre/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , SARS-CoV-2
12.
J Am Soc Nephrol ; 31(10): 2372-2391, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32737144

RESUMO

BACKGROUND: Maintenance of the intricate interdigitating morphology of podocytes is crucial for glomerular filtration. One of the key aspects of specialized podocyte morphology is the segregation and organization of distinct cytoskeletal filaments into different subcellular components, for which the exact mechanisms remain poorly understood. METHODS: Cells from rats, mice, and humans were used to describe the cytoskeletal configuration underlying podocyte structure. Screening the time-dependent proteomic changes in the rat puromycin aminonucleoside-induced nephropathy model correlated the actin-binding protein LIM-nebulette strongly with glomerular function. Single-cell RNA sequencing and immunogold labeling were used to determine Nebl expression specificity in podocytes. Automated high-content imaging, super-resolution microscopy, atomic force microscopy (AFM), live-cell imaging of calcium, and measurement of motility and adhesion dynamics characterized the physiologic role of LIM-nebulette in podocytes. RESULTS: Nebl knockout mice have increased susceptibility to adriamycin-induced nephropathy and display morphologic, cytoskeletal, and focal adhesion abnormalities with altered calcium dynamics, motility, and Rho GTPase activity. LIM-nebulette expression is decreased in diabetic nephropathy and FSGS patients at both the transcript and protein level. In mice, rats, and humans, LIM-nebulette expression is localized to primary, secondary, and tertiary processes of podocytes, where it colocalizes with focal adhesions as well as with vimentin fibers. LIM-nebulette shRNA knockdown in immortalized human podocytes leads to dysregulation of vimentin filament organization and reduced cellular elasticity as measured by AFM indentation. CONCLUSIONS: LIM-nebulette is a multifunctional cytoskeletal protein that is critical in the maintenance of podocyte structural integrity through active reorganization of focal adhesions, the actin cytoskeleton, and intermediate filaments.


Assuntos
Actinas/fisiologia , Filamentos Intermediários/fisiologia , Nefropatias/patologia , Glomérulos Renais/patologia , Podócitos/patologia , Vimentina/fisiologia , Animais , Técnicas de Cultura de Células , Proteínas do Citoesqueleto/fisiologia , Humanos , Nefropatias/etiologia , Proteínas com Domínio LIM/fisiologia , Camundongos , Ratos
13.
Int J Mol Sci ; 22(3)2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33525632

RESUMO

Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) is a novel epidemic strain of Betacoronavirus that is responsible for the current viral pandemic, coronavirus disease 2019 (COVID-19), a global health crisis. Other epidemic Betacoronaviruses include the 2003 SARS-CoV-1 and the 2009 Middle East Respiratory Syndrome Coronavirus (MERS-CoV), the genomes of which, particularly that of SARS-CoV-1, are similar to that of the 2019 SARS-CoV-2. In this extensive review, we document the most recent information on Coronavirus proteins, with emphasis on the membrane proteins in the Coronaviridae family. We include information on their structures, functions, and participation in pathogenesis. While the shared proteins among the different coronaviruses may vary in structure and function, they all seem to be multifunctional, a common theme interconnecting these viruses. Many transmembrane proteins encoded within the SARS-CoV-2 genome play important roles in the infection cycle while others have functions yet to be understood. We compare the various structural and nonstructural proteins within the Coronaviridae family to elucidate potential overlaps and parallels in function, focusing primarily on the transmembrane proteins and their influences on host membrane arrangements, secretory pathways, cellular growth inhibition, cell death and immune responses during the viral replication cycle. We also offer bioinformatic analyses of potential viroporin activities of the membrane proteins and their sequence similarities to the Envelope (E) protein. In the last major part of the review, we discuss complement, stimulation of inflammation, and immune evasion/suppression that leads to CoV-derived severe disease and mortality. The overall pathogenesis and disease progression of CoVs is put into perspective by indicating several stages in the resulting infection process in which both host and antiviral therapies could be targeted to block the viral cycle. Lastly, we discuss the development of adaptive immunity against various structural proteins, indicating specific vulnerable regions in the proteins. We discuss current CoV vaccine development approaches with purified proteins, attenuated viruses and DNA vaccines.


Assuntos
Betacoronavirus/fisiologia , Infecções por Coronavirus/metabolismo , Proteínas da Matriz Viral/metabolismo , Animais , Betacoronavirus/genética , Betacoronavirus/imunologia , COVID-19/imunologia , COVID-19/metabolismo , COVID-19/patologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/patologia , Genoma Viral , Interações Hospedeiro-Patógeno , Humanos , Evasão da Resposta Imune , Mapas de Interação de Proteínas , SARS-CoV-2/genética , SARS-CoV-2/imunologia , SARS-CoV-2/fisiologia , Proteínas da Matriz Viral/genética , Proteínas da Matriz Viral/imunologia , Internalização do Vírus , Replicação Viral
14.
Angew Chem Int Ed Engl ; 60(35): 19183-19190, 2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-33928733

RESUMO

Lithium metal anode holds great promises for next-generation battery technologies but is notoriously difficult to work with. The key to solving this challenge is believed to lie in the ability of forming stable solid-electrolyte interphase (SEI) layers. To further address potential safety issues, it is critical to achieve this goal in nonflammable electrolytes. Building upon previous successes in forming stable SEI in conventional carbonate-based electrolytes, here we report that reversible Li stripping/plating could be realized in triethyl phosphate (TEP), a known flame retardant. The critical enabling factor of our approach was the introduction of oxygen, which upon electrochemical reduction induces the initial decomposition of TEP and produces Li3 PO4 and poly-phosphates. Importantly, the reaction was self-limiting, and the resulting material regulated Li plating by limiting dendrite formation. In effect, we obtained a functional SEI on Li metal in a nonflammable electrolyte. When tested in a symmetric Li∥Li cell, more than 300 cycles of stripping/plating were measured at a current density of 0.5 mA cm-2 . Prototypical Li-O2 and Li-ion batteries were also fabricated and tested to further support the effectiveness of this strategy. The mechanism by which the SEI forms was studied by density functional theory (DFT), and the predictions were corroborated by the successful detection of the intermediates and products.

16.
Angew Chem Int Ed Engl ; 58(43): 15313-15317, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31478284

RESUMO

The incompatibility between the anode and the cathode chemistry limits the used of Mg as an anode. This issue may be addressed by separating the anolyte and the catholyte with a membrane that only allows for Mg2+ transport. Mg-MOF-74 thin films were used as the separator for this purpose. It was shown to meet the needs of low-resistance, selective Mg2+ transport. The uniform MOF thin films supported on Au substrate with thicknesses down to ca. 202 nm showed an intrinsic resistance as low as 6.4â€…Ω cm2 , with the normalized room-temperature ionic conductivity of ca. 3.17×10-6  S cm-1 . When synthesized directly onto a porous anodized aluminum oxide (AAO) support, the resulting films were used as a standalone membrane to permit stable, low-overpotential Mg striping and plating for over 100 cycles at a current density of 0.05 mA cm-2 . The film was effective in blocking solvent molecules and counterions from crossing over for extended period of time.

18.
Chemistry ; 24(12): 2837-2840, 2018 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-29164727

RESUMO

A practical synthesis of the complex payload for an anti-Staphylococcus aureus THIOMABTM antibody-antibiotic conjugate (TAC) is described. The route takes advantage of a delicate oxidative condensation, achieved using a semi-continuous flow procedure. It allows for the generation of kilogram quantities of a key intermediate to enable a mild nucleophilic aromatic substitution to the tertiary amine free drug. The linker component is introduced as a benzylic chloride, which allows formation of the quaternary ammonium salt linker-drug. This chemical process surmounts numerous synthetic challenges and navigates deeply colored and unstable compounds to support clinical studies to counter S. aureus bacterial infections.


Assuntos
Antibacterianos/farmacologia , Imunoconjugados/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/química , Testes de Sensibilidade Microbiana , Compostos de Amônio Quaternário/farmacologia , Staphylococcus aureus/efeitos dos fármacos
19.
Biochim Biophys Acta ; 1862(4): 556-565, 2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-26692170

RESUMO

Cervical cancer is caused by infections with human papillomaviruses (HPV) and genetic alternations in the cervical epithelium. While the former is well studied, the latter remains unclear. We report here that CYB5D2/Neuferricin possesses tumor suppressing activity towards cervical tumorigenesis. Ectopic expression of CYB5D2 did not affect HeLa cell proliferation and the cell's ability to form xenograft tumors, but significantly inhibited HeLa cell invasion in vitro and the cell-produced lung metastasis in NOD/SCID mice. Knockdown of CYB5D2 enhanced HeLa cell invasion. Two mutations in CYB5D2, the substitutions of arginine (R) 7 with either proline (P) or glycine (G), were reported in colon cancer. Both CYB5D2(R7P) and CYB5D2(R7G) were incapable of inhibiting HeLa cell invasion. CYB5D2 binds heme, in which aspartate (D) 86 is required. While CYB5D2(D86G) is heme-binding defective, it inhibited HeLa cell invasion. On the other hand, CYB5D2(R7P) and CYB5D2(R7G) bound heme but did not inhibit HeLa cell invasion. Collectively, CYB5D2 inhibits HeLa cell invasion independently of its heme binding. Furthermore, immunohistochemistry examination of CYB5D2 expression in 20 normal cervical tissues and 40 cervical squamous cell carcinomas (SCC) revealed a CYB5D2 reduction in 87.5% (35/40) of SCC. Analysis of CYB5D2 gene expression and genomic alteration data available from Oncomeine™ detected significant reductions of CYB5D2 mRNA in 40 SCCs and CYB5D2 gene copy number in 107 SCCs. Collectively, we provide evidence that CYB5D2 is a candidate tumor suppressor of cervical tumorigenesis.


Assuntos
Citocromos b5/biossíntese , Regulação Neoplásica da Expressão Gênica , Proteínas Supressoras de Tumor/biossíntese , Neoplasias do Colo do Útero/enzimologia , Animais , Citocromos b5/genética , Feminino , Técnicas de Silenciamento de Genes , Células HEK293 , Células HeLa , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Mutação , Invasividade Neoplásica , Proteínas Supressoras de Tumor/genética , Neoplasias do Colo do Útero/genética
20.
BMC Geriatr ; 17(1): 193, 2017 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-28851278

RESUMO

BACKGROUND: Elderly patients have a long list of differentials for causes of acute confusion and altered consciousness levels, including infectious agents. In addition, elderly, retired patients often have more time to travel for tourism, particularly to exotic, warmer locations. Mediterranean countries such as Spain and Italy are popular holiday destinations for British and other tourists, especially during the winter months. However, these warm climates allow insect vectors to proliferate, increasing the risk of exposure to endemic vectorborne viral infections whilst on vacation. Such infections may not be routinely considered by geriatric medical teams. CASE PRESENTATION: An 87-year old gentleman presented with a three-day history of worsening confusion, lethargy, ataxia, and fevers following a trip to Spain, where he may have sustained a sandfly bite. By the time of admission, he had a reduced GCS, was hallucinating, and was incontinent of urine and faeces, though blood pressure and heart rate were normal. He also appeared hyperaesthetic, and found even capillary blood sugar testing extremely painful. He had no history of cognitive defect or other neurological conditions. He had been previously independently active, with frequent trips to Spain where he maintained a holiday home. He probably sustained a sandfly bite during this most recent trip, whilst cleaning out a shed. Acute and convalescent sera demonstrated IgG antibodies to Toscana virus at extremely high titres of ≥1:10,000 by immunofluorescence assay, though no Toscana virus RNA was detectable in these sera by the time of presentation. CONCLUSIONS: Toscana virus should be included in the differential diagnosis of any patients presenting with meningo-encephalitis who have recently returned from a Mediterranean country. Testing for Toscana virus infection is performed by serological testing on acute/convalescent paired sera, and/or a polymerase chain reaction (PCR) assay on blood or cerebrospinal fluid (CSF) if presenting within 5 days of illness onset. Making a diagnosis of Toscana virus meningitis/encephalitis (where no other pathogen is detected) has additional clinical utility in reducing or preventing unnecessary use of antibiotics, as well as reassuring the patient and family that generally, this illness is generally self-limiting and full recovery within a few weeks is expected, as in the case reported here.


Assuntos
Meningoencefalite/diagnóstico , Febre por Flebótomos/diagnóstico , Vírus da Febre do Flebótomo Napolitano/isolamento & purificação , Doença Relacionada a Viagens , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Humanos , Masculino , Região do Mediterrâneo , Meningoencefalite/virologia , Febre por Flebótomos/virologia , Espanha
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