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1.
Stem Cell Reports ; 18(5): 1107-1122, 2023 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-37084725

RESUMEN

Although lung disease is the primary clinical outcome in COVID-19 patients, how SARS-CoV-2 induces lung pathology remains elusive. Here we describe a high-throughput platform to generate self-organizing and commensurate human lung buds derived from hESCs cultured on micropatterned substrates. Lung buds resemble human fetal lungs and display proximodistal patterning of alveolar and airway tissue directed by KGF. These lung buds are susceptible to infection by SARS-CoV-2 and endemic coronaviruses and can be used to track cell type-specific cytopathic effects in hundreds of lung buds in parallel. Transcriptomic comparisons of infected lung buds and postmortem tissue of COVID-19 patients identified an induction of BMP signaling pathway. BMP activity renders lung cells more susceptible to SARS-CoV-2 infection and its pharmacological inhibition impairs infection by this virus. These data highlight the rapid and scalable access to disease-relevant tissue using lung buds that recapitulate key features of human lung morphogenesis and viral infection biology.


Asunto(s)
COVID-19 , Humanos , SARS-CoV-2 , Pulmón , Células Cultivadas
3.
J Autism Dev Disord ; 52(12): 5308-5320, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34981308

RESUMEN

This paper describes a process to define a comprehensive list of exemplars for seven core Diagnostic and Statistical Manual (DSM) diagnostic criteria for autism spectrum disorder (ASD), and report on interrater reliability in applying these exemplars to determine ASD case classification. Clinicians completed an iterative process to map specific exemplars from the CDC Autism and Developmental Disabilities Monitoring (ADDM) Network criteria for ASD surveillance, DSM-5 text, and diagnostic assessments to each of the core DSM-5 ASD criteria. Clinicians applied the diagnostic exemplars to child behavioral descriptions in existing evaluation records to establish initial reliability standards and then for blinded clinician review in one site (phase 1) and for two ADDM Network surveillance years (phase 2). Interrater reliability for each of the DSM-5 diagnostic categories and overall ASD classification was high (defined as very good .60-.79 to excellent ≥ .80 Kappa values) across sex, race/ethnicity, and cognitive levels for both phases. Classification of DSM-5 ASD by mapping specific exemplars from evaluation records by a diverse group of clinician raters is feasible and reliable. This framework provides confidence in the consistency of prevalence classifications of ASD and may be further applied to improve consistency of ASD diagnoses in clinical settings.


Asunto(s)
Trastorno del Espectro Autista , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Selección de Paciente , Niño , Humanos , Trastorno del Espectro Autista/diagnóstico , Trastorno del Espectro Autista/epidemiología , Vigilancia de la Población , Prevalencia , Reproducibilidad de los Resultados
4.
Nat Plants ; 7(6): 725-729, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34099902

RESUMEN

Recent carbon dioxide (CO2) concentrations promoted higher parthenin concentrations in an invasive Parthenium hysterophorus biotype. Mean concentrations of parthenin, an allelopathic and defensive sesquiterpene lactone, were 49% higher at recent (~400 ppm) than at mid-twentieth-century (~300 ppm) CO2 concentrations, but did not vary in a non-invasive biotype, suggesting that recent increases in atmospheric CO2 may have already altered the chemistry of this destructive weed, potentially contributing to its invasive success.


Asunto(s)
Asteraceae/metabolismo , Dióxido de Carbono , Malezas/metabolismo , Sesquiterpenos/metabolismo , Alelopatía , Asteraceae/fisiología , Ecotipo , Especies Introducidas , Brotes de la Planta/metabolismo , Malezas/fisiología , Toxinas Biológicas/metabolismo
6.
J Neurol ; 268(6): 2175-2184, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33484325

RESUMEN

There is increasing interest in the development of multiple sclerosis (MS) biomarkers that reflect central nervous system tissue injury to determine prognosis. We aimed to assess the prognostic value of kinesin superfamily motor protein KIF5A in MS by measuring levels of KIF5A in cerebrospinal fluid (CSF) combined with analysis of single nucleotide polymorphisms (SNPs; rs12368653 and rs703842) located within a MS susceptibility gene locus at chromosome 12q13-14 region. Enzyme-linked immunosorbent assay was used to measure KIF5A in CSF obtained from two independent biobanks comprising non-inflammatory neurological disease controls (NINDC), clinically isolated syndrome (CIS) and MS cases. CSF KIF5A expression was significantly elevated in progressive MS cases compared with NINDCs, CIS and relapsing-remitting MS (RRMS). In addition, levels of KIF5A positively correlated with change in MS disease severity scores (EDSS, MSSS and ARMSSS), in RRMS patients who had documented disease progression at 2-year clinical follow-up. Copies of adenine risk alleles (AG/AA; rs12368653 and rs703842) corresponded with a higher proportion of individuals in relapse at the time of lumbar puncture (LP), higher use of disease-modifying therapies post LP and shorter MS duration. Our study suggests that CSF KIF5A has potential as a predictive biomarker in MS and further studies into the potential prognostic value of analysing MS susceptibility SNPs should be considered.


Asunto(s)
Cinesinas , Esclerosis Múltiple Crónica Progresiva , Esclerosis Múltiple Recurrente-Remitente , Esclerosis Múltiple , Biomarcadores , Progresión de la Enfermedad , Genotipo , Humanos , Cinesinas/genética , Esclerosis Múltiple/diagnóstico , Esclerosis Múltiple/genética , Esclerosis Múltiple Recurrente-Remitente/genética
7.
bioRxiv ; 2021 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-33442697

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of the global COVID-19 pandemic and the lack of therapeutics hinders pandemic control1-2. Although lung disease is the primary clinical outcome in COVID-19 patients1-3, how SARS-CoV-2 induces tissue pathology in the lung remains elusive. Here we describe a high-throughput platform to generate tens of thousands of self-organizing, nearly identical, and genetically matched human lung buds derived from human pluripotent stem cells (hPSCs) cultured on micropatterned substrates. Strikingly, in vitro-derived human lung buds resemble fetal human lung tissue and display in vivo-like proximo-distal coordination of alveolar and airway tissue differentiation whose 3D epithelial self-organization is directed by the levels of KGF. Single-cell transcriptomics unveiled the cellular identities of airway and alveolar tissue and the differentiation of WNThi cycling alveolar stem cells, a human-specific lung cell type4. These synthetic human lung buds are susceptible to infection by SARS-CoV-2 and endemic coronaviruses and can be used to track cell type-dependent susceptibilities to infection, intercellular transmission and cytopathology in airway and alveolar tissue in individual lung buds. Interestingly, we detected an increased susceptibility to infection in alveolar cells and identified cycling alveolar stem cells as targets of SARS-CoV-2. We used this platform to test neutralizing antibodies isolated from convalescent plasma that efficiently blocked SARS-CoV-2 infection and intercellular transmission. Our platform offers unlimited, rapid and scalable access to disease-relevant lung tissue that recapitulate key hallmarks of human lung development and can be used to track SARS-CoV-2 infection and identify candidate therapeutics for COVID-19.

8.
QJM ; 114(1): 32-38, 2021 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-32866245

RESUMEN

BACKGROUND: Up to half of patients presenting with falls, syncope or dizziness are admitted to hospital. Many are discharged without a clear diagnosis for their index episode, however, and therefore a relatively high risk of readmission. AIM: To examine the impact of ED-FASS (Emergency Department Falls and Syncope Service) a dedicated specialist service embedded within an ED, seeing patients of all ages with falls, syncope and dizziness. DESIGN: Pre- and post-cohort study. METHODS: Admission rates, length of stay (LOS) and readmission at 3 months were examined for all patients presenting with a fall, syncope or dizziness from April to July 2018 (pre-ED-FASS) inclusive and compared to April to July 2019 inclusive (post-ED-FASS). RESULTS: There was a significantly lower admission rate for patients presenting in 2019 compared to 2018 [27% (453/1676) vs. 34% (548/1620); X2 = 18.0; P < 0.001], with a 20% reduction in admissions. The mean LOS for patients admitted in 2018 was 20.7 [95% confidence interval (CI) 17.4-24.0] days compared to 18.2 (95% CI 14.6-21.9) days in 2019 (t = 0.98; P = 0.3294). This accounts for 11 344 bed days in the 2018 study period, and 8299 bed days used after ED-FASS. There was also a significant reduction in readmission rates within 3 months of index presentation, from 21% (109/1620) to 16% (68/1676) (X2 = 4.68; P = 0.030). CONCLUSION: This study highlights the significant potential benefits of embedding dedicated multidisciplinary services at the hospital front door in terms of early specialist assessment and directing appropriate patients to effective ambulatory care pathways.


Asunto(s)
Accidentes por Caídas , Mareo , Readmisión del Paciente , Estudios de Cohortes , Servicio de Urgencia en Hospital , Humanos , Tiempo de Internación , Estudios Retrospectivos , Síncope
10.
Eur J Neurol ; 27(12): 2430-2438, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32657501

RESUMEN

BACKGROUND AND PURPOSE: Ischaemic and hemorrhagic strokes are dreaded complications of infective endocarditis (IE). The timing of valve surgery for IE patients with stroke remains uncertain. The aim was to study perioperative neurological complications in relation to surgical timing. METHODS: The study cohort consisted of patients diagnosed with acute IE from January 2010 to December 2016. Early surgery was defined as valve surgery within 14 days of IE diagnosis, and late surgery as after 14 days. Neurological complications that occurred within 14 days post-surgery were considered perioperative and classified as new ischaemic stroke or hemorrhagic stroke, expansion of an existing intracranial hemorrhage and new-onset seizures. Perioperative neurological complications were compared by surgical timing and other variables, including pre-surgical imaging. RESULTS: Overall, 183 patients underwent valve surgery: 92 had early surgery at a median of 8 days (interquartile range 6-11); 91 had late surgery at a median of 28 days (interquartile range 19-50). Twenty patients (10.9%) had 24 complications: 11 ischaemic, six intraparenchymal hemorrhages, three subarachnoid hemorrhages (SAHs) and four new-onset seizures. Rates of neurological complications were similar for early and late surgery groups (10.9% vs. 11%). Enterococcal IE was more common amongst patients with perioperative neurological complications (35% vs. 12.3%, P < 0.01). An acute infarct was present on pre-surgical magnetic resonance imaging of 134 patients (74%) and was not associated with perioperative neurological complications. Thirty-five patients (19.3%) had intracranial hemorrhage on pre-surgical imaging. SAH on pre-surgical imaging was associated with developing SAH perioperatively (66.7% vs. 13.5%, P < 0.01). CONCLUSION: Early valve surgery for patients with IE complicated by stroke was not associated with perioperative neurological complications.


Asunto(s)
Isquemia Encefálica , Procedimientos Quirúrgicos Cardíacos , Endocarditis Bacteriana , Accidente Cerebrovascular , Isquemia Encefálica/complicaciones , Humanos , Estudios Retrospectivos , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico por imagen , Resultado del Tratamiento
11.
J Neurophysiol ; 123(3): 1113-1119, 2020 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-31995434

RESUMEN

Blood flow occlusion (BFO) has been used to study the influence of group III/IV muscle afferents after fatiguing exercise, but it is unknown how BFO-induced activity of these afferents affects motor cortical and motoneuronal excitability during low-intensity exercise. Therefore, the purpose of this study was to assess the acute effect of BFO on peripheral [maximal M wave (Mmax)], spinal [cervicomedullary motor evoked potential (CMEP) normalized to Mmax], and motor cortical [motor evoked potential (MEP) normalized to CMEP] excitability. Nine healthy men completed a sustained isometric contraction of the elbow flexors at 20% of maximal force under three conditions: 1) contractile failure with BFO, 2) a time-matched trial without restriction [free flow (FFiso)], and 3) contractile failure with free flow (FFfail). Time to failure for BFO (and FFiso) were ~80% shorter than that for FFfail (P < 0.05). For FFfail and FFiso, Mmax area decreased ~17% and ~7%, respectively (P < 0.05), with no change during BFO. CMEP/Mmax area increased ~226% and ~80% during BFO and FFfail, respectively (P < 0.05), with no change during FFiso (P > 0.05). The increase in normalized CMEP area was greater for BFO and FFfail compared with FFiso and for BFO compared with FFfail. MEP/CMEP area was not different among the protocols (P > 0.05) and increased ~64% with time (P < 0.05). It is likely that group III/IV muscle afferent feedback to the spinal cord modulates the large increase in motoneuronal excitability for the BFO compared with FFfail and FFiso protocols.NEW & NOTEWORTHY We have observed how blood flow occlusion modulates motor cortical, spinal, and peripheral excitability during and immediately after a sustained low-intensity isometric elbow flexion contraction to failure. We conclude that blood flow occlusion causes a greater and more rapid increase in motoneuronal excitability.


Asunto(s)
Médula Cervical/fisiología , Codo/fisiología , Potenciales Evocados Motores/fisiología , Contracción Isométrica/fisiología , Corteza Motora/fisiología , Neuronas Motoras/fisiología , Músculo Esquelético/fisiología , Flujo Sanguíneo Regional/fisiología , Adulto , Estimulación Eléctrica , Humanos , Masculino , Fatiga Muscular/fisiología , Músculo Esquelético/irrigación sanguínea , Estimulación Magnética Transcraneal , Adulto Joven
12.
Eur J Neurol ; 25(7): 970-975, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29603515

RESUMEN

BACKGROUND AND PURPOSE: Magnetic resonance imaging (MRI) features such as cerebral microbleeds and sulcal susceptibility-weighted imaging (SWI) or gradient-echo T2* lesions in infective endocarditis (IE) have been associated with the presence of infectious intracranial aneurysm (IIA). Our aim was to validate these MRI predictors for IIA in order to better assist in assessing the appropriate indications for digital subtraction angiography (DSA). METHODS: The derivation cohort comprised IE patients with neurological evaluation, MRI and DSA at a single tertiary referral center from January 2015 to July 2016. Validation was performed in a cohort of IE patients who underwent MRI and DSA at the same center from 2010 to 2014. RESULTS: Of 62 patients in the derivation cohort, 10 (16%) had IIAs. Of 129 in the validation cohort, 19 (15%) IIAs were identified. The MRI predictors for IIA consist of (i) contrast enhancement with microbleeds, (ii) cerebral microbleeds >5 mm or sulcal SWI lesions and (iii) any MRI hemorrhages. The sensitivity for the presence of IIA in each group of the derivation cohort was 90%, 80% and 100%, respectively. The sensitivity in the validation cohort was 47%, 68% and 94% respectively. The specificity in the derivation cohort was 87%, 85% and 18%. In the validation cohort, the specificity was similar at 87%, 75% and 27%. CONCLUSIONS: The absence of MRI hemorrhages may not necessitate the need for DSA.


Asunto(s)
Hemorragia Cerebral/complicaciones , Endocarditis/complicaciones , Aneurisma Intracraneal/etiología , Hemorragia Cerebral/diagnóstico por imagen , Endocarditis/diagnóstico por imagen , Humanos , Aneurisma Intracraneal/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Estudios Retrospectivos , Sensibilidad y Especificidad , Centros de Atención Terciaria
14.
Invest New Drugs ; 35(3): 324-333, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28150073

RESUMEN

Introduction This was an open-label, dose escalation (3 + 3 design), Phase I study of SOR-C13 in patients with advanced tumors of epithelial origin. Primary objectives were to assess safety/tolerability and pharmacokinetics. Secondary goals were to assess pharmacodynamics and efficacy of SOR-C13. Methods SOR-C13 was administered IV QD on days 1-3 and 8-10 of a 21-day cycle. Doses were 2.75 and 5.5 mg/kg (20-min infusion) and 1.375, 2.75, 4.13 and 6.2 mg/kg (90-min infusion). Toxicity was assessed by National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) version 4.0. Dose limiting toxicity (DLT) was assessed within the first treatment cycle. Tumors were evaluated, using Response Evaluation Criteria in Solid Tumors (RECIST) 1.1, after two cycles. Results Twenty-three patients were treated. No drug-related serious adverse events occurred. DLTs occurred in six patients: asymptomatic, drug-related, transient Grade 2 hypocalcemia (4 patients), and unrelated Grade 3 anemia and Grade 3 atrial fibrillation, 1 patient each. Calcium and vitamin D supplementation eliminated further Grade 2 hypocalcemia. One Grade 3 treatment emergent adverse event, urticaria, was definitely related to SOR-C13. Four possibly drug-related, Grade 3 events (alanine aminotransferase and aspartate aminotransferase elevation, headache, and hypokalemia) were observed. Of 22 evaluable patients, 54.5% showed stable disease ranging from 2.8 to 12.5 months. The best response was a 27% reduction in a pancreatic tumor with a 55% reduction in CA19-9 levels at 6.2 mg/kg. Conclusion SOR-C13 was safe and tolerated up to 6.2 mg/kg. The Maximal Tolerated Dose (MTD) was not established. Stable disease suggested antitumor activity.


Asunto(s)
Antineoplásicos , Bloqueadores de los Canales de Calcio , Neoplasias/tratamiento farmacológico , Canales Catiónicos TRPV/antagonistas & inhibidores , Adulto , Anciano , Alanina Transaminasa/sangre , Antineoplásicos/efectos adversos , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Aspartato Aminotransferasas/sangre , Bloqueadores de los Canales de Calcio/efectos adversos , Bloqueadores de los Canales de Calcio/farmacocinética , Bloqueadores de los Canales de Calcio/farmacología , Bloqueadores de los Canales de Calcio/uso terapéutico , Canales de Calcio/genética , Femenino , Cefalea/inducido químicamente , Humanos , Hipocalcemia/inducido químicamente , Hipopotasemia/inducido químicamente , Queratina-18/sangre , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Neoplasias/metabolismo , Péptidos/efectos adversos , Péptidos/farmacocinética , Péptidos/farmacología , Péptidos/uso terapéutico , ARN Mensajero/sangre , Canales Catiónicos TRPV/efectos adversos , Canales Catiónicos TRPV/genética , Canales Catiónicos TRPV/farmacocinética , Canales Catiónicos TRPV/farmacología , Canales Catiónicos TRPV/uso terapéutico , Resultado del Tratamiento , Urticaria/inducido químicamente
15.
Neuropathol Appl Neurobiol ; 43(3): 227-241, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26785938

RESUMEN

AIMS: Understanding the causes of axonal pathology remains a key goal in the pursuit of new therapies to target disease progression in multiple sclerosis (MS). Anterograde axonal transport of many proteins vital for axonal viability is mediated by the motor protein KIF5A, which has been linked to several neurological diseases. This study aimed to investigate the expression of KIF5A protein and its associated cargoes: amyloid precursor protein (APP) and neurofilament (NF) in post mortem MS and control white matter (WM) and to determine if KIF5A expression is influenced by the presence of MS risk single nucleotide polymorphisms (SNPs) identified in the region of the KIF5A gene. METHODS: Using immunoblotting assays we analysed the expression of KIF5A, APP and NF phospho-isoforms in 23 MS cases and 12 controls. RESULTS: We found a significant reduction in KIF5A and associated cargoes in MS WM and an inverse correlation between KIF5A and APP/NF protein levels. Furthermore, homozygous carriers of MS risk gene SNPs show significantly lower levels of KIF5A protein compared to MS patients with no copies of the risk SNPs. CONCLUSIONS: We conclude that reduced expression of axonal motor KIF5A may have important implications in determining axonal transport deficits and ongoing neurodegeneration in MS.


Asunto(s)
Axones/metabolismo , Cinesinas/genética , Esclerosis Múltiple/genética , Esclerosis Múltiple/patología , Sustancia Blanca/patología , Adulto , Anciano , Axones/patología , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/metabolismo , Proteínas de Neurofilamentos/metabolismo , Polimorfismo de Nucleótido Simple , Transporte de Proteínas/genética , Sustancia Blanca/metabolismo
16.
BMJ Case Rep ; 20162016 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-27702933

RESUMEN

We report a case of Erdheim-Chester disease (ECD) with a 25-year history following initial presentation with diabetes insipidus and brainstem involvement. The exceptionally long history is particularly notable, given that ECD is a life-threatening disorder and there is a recognised association between central nervous system involvement and poor outcome. The case is a timely reminder of the presenting features of the condition, given the emergence of potential new treatment options.


Asunto(s)
Encefalopatías/etiología , Enfermedad de Erdheim-Chester/complicaciones , Diabetes Insípida/complicaciones , Resultado Fatal , Femenino , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad
17.
Pract Neurol ; 16(6): 496-499, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27651498

RESUMEN

Ovarioleukodystrophy-the co-occurrence of leukodystrophy and premature ovarian failure-is a rare presentation now recognised to be part of the clinical spectrum of vanishing white matter disease. We describe a woman with epilepsy and neuroimaging changes consistent with leukoencephalopathy who presented with non-convulsive status epilepticus after starting hormone replacement therapy in the context of premature ovarian failure. Genetic testing confirmed her to be a compound heterozygote for EIF2B5 mutations; the gene encodes a subunit of eukaryotic translation initiation factor 2B. Mutations in EIF2B1-5 result in vanishing white matter disease. We highlight the importance of ovarian failure as a diagnostic pointer to eukaryotic translation initiation factor 2B (eIF2B)-related ovarioleukodystrophy and present a brief literature review of ovarioleukodystrophy.


Asunto(s)
Factor 2B Eucariótico de Iniciación/genética , Leucoencefalopatías/genética , Enfermedades del Ovario/genética , Adulto , Femenino , Humanos , Leucoencefalopatías/diagnóstico , Mutación , Enfermedades del Ovario/diagnóstico , Adulto Joven
18.
Pract Neurol ; 16(3): 240-2, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26856357

RESUMEN

IgG4-related disease (IgG4-RD) is a newly recognised, multiorgan, inflammatory disease, and its full clinical spectrum remains undefined. We present a biopsy-proven case of IgG4-RD presenting with a parapharyngeal mass with intracranial extension and possible involvement of the brain parenchyma. We highlight the importance of considering the diagnosis in those presenting with tumefactive lesions, leptomeningitis or pachymeningitis and emphasise the value of securing a tissue diagnosis so that appropriate long-term treatment can be instigated and complications avoided.


Asunto(s)
Enfermedades Autoinmunes/complicaciones , Inmunoglobulina G , Base del Cráneo/patología , Biopsia , Humanos , Masculino , Meningitis , Persona de Mediana Edad
19.
J Phys Chem A ; 120(27): 4805-11, 2016 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-26837823

RESUMEN

Four electronic systems with origin bands at 759.5, 559.3, 476.3, and 385.5 nm are detected in a 6 K neon matrix following deposition of mass-selected protonated fluoranthene C16H11(+) produced from a reaction of neutral vapor and ethanol in a hot-cathode ion source. Two cationic isomers are identified as the carriers of these band systems. The 559.3, 476.3, and 385.5 nm absorptions are assigned to 4,3,2 (1)A' ← X (1)A' transitions of isomer E(+) (γ-) and the 2 (1)A' ← X (1)A' system at 759.5 nm is of isomer C(+) (α-) of protonated fluoranthene on the basis of theoretical predictions. The electronic spectrum of E(+) was also recorded in the gas phase using a resonant 1 + 1 two-photon excitation-dissociation technique in an ion trap at vibrational and rotational temperatures of 10 K. The 3,2 (1)A' ← X (1)A' transitions have origin band maxima at 558.28 ± 0.01 and 474.92 ± 0.01 nm. Both the 2 (1)A' and 3 (1)A' excited states have a distinct vibrational pattern with lifetimes on the order of 1 ps.

20.
Org Biomol Chem ; 14(6): 2134-44, 2016 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-26762685

RESUMEN

Sixteen new isothiazoloisoxazole 1,1-dioxides, one new isothiazolotriazole and one new isothiazolopyrazole have been synthesised by using 1,3-dipolar cycloadditions to isothiazole 1,1-dioxides. One sub-set of these isothiazoloisoxazoles showed low µM activity against a human breast carcinoma cell line, whilst a second sub-set plus the isothiazolotriazole demonstrated an interesting restricted rotation of sterically hindered bridgehead substituents. A thiazete 1,1-dioxide produced from one of the isothiazole 1,1-dioxides underwent conversion into an unknown 1,2,3-oxathiazolin-2-oxide upon treatment with Lewis acids, but was inert towards 1,3-dipoles and cyclopropenones. Six supporting crystal structures are included.


Asunto(s)
Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Isoxazoles/farmacología , Tiazoles/farmacología , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Isoxazoles/síntesis química , Isoxazoles/química , Células MCF-7 , Conformación Molecular , Relación Estructura-Actividad , Tiazoles/síntesis química , Tiazoles/química
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