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1.
J Am Chem Soc ; 146(25): 17325-17333, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38865257

RESUMEN

Titanium-oxo clusters can undergo photochemical reactions under UV light, resulting in the reduction of the titanium-oxo core and oxidation of surface ligands. This is an important step in photocatalytic processes in light-absorbing Ti/O-based clusters, metal-organic frameworks, and (nano)material surfaces; however, studying the direct outcome of this photochemical process is challenging due to the fragility of the immediate photoproducts. In this report, titanium-oxo clusters [TiO(OiPr)(L)]n (n = 4, L = O2PPh2, or n = 6, L = O2CCH2tBu) undergo a two-electron photoredox reaction in the single-crystal state via an irreversible single-crystal to single-crystal (SC-SC) transformation initiated by a UV laser. The process is monitored by single crystal X-ray diffraction revealing the photoreduction of the cluster with coproduction of an (oxidized) acetone ligand, which is retained in the structure as a ligand to Ti(3+). The results demonstrate that photochemistry of inorganic molecules can be studied in the single crystal phase, allowing characterization of photoproducts which are unstable in the solution phase.

2.
J Am Chem Soc ; 146(5): 3270-3278, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38275220

RESUMEN

Living on an increasingly polluted planet, the removal of toxic pollutants such as sulfur dioxide (SO2) from the troposphere and power station flue gas is becoming more and more important. The CPO-27/MOF-74 family of metal-organic frameworks (MOFs) with their high densities of open metal sites is well suited for the selective adsorption of gases that, like SO2, bind well to metals and have been extensively researched both practically and through computer simulations. However, until now, focus has centered upon the binding of SO2 to the open metal sites in this MOF (called chemisorption, where the adsorbent-adsorbate interaction is through a chemical bond). The possibility of physisorption (where the adsorbent-adsorbate interaction is only through weak intermolecular forces) has not been identified experimentally. This work presents an in situ single-crystal X-ray diffraction (scXRD) study that identifies discrete adsorption sites within Ni-MOF-74/Ni-CPO-27, where SO2 is both chemisorbed and physisorbed while also probing competitive adsorption of SO2 of these sites when water is present. Further features of this site have been confirmed by variable SO2 pressure scXRD studies, DFT calculations, and IR studies.

3.
Am J Physiol Heart Circ Physiol ; 326(3): H724-H734, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38214908

RESUMEN

Scn5a heterozygous null (Scn5a+/-) mice have historically been used to investigate arrhythmogenic mechanisms of diseases such as Brugada syndrome (BrS) and Lev's disease. Previously, we demonstrated that reducing ephaptic coupling (EpC) in ex vivo hearts exacerbates pharmacological voltage-gated sodium channel (Nav)1.5 loss of function (LOF). Whether this effect is consistent in a genetic Nav1.5 LOF model is yet to be determined. We hypothesized that loss of EpC would result in greater reduction in conduction velocity (CV) for the Scn5a+/- mouse relative to wild type (WT). In vivo ECGs and ex vivo optical maps were recorded from Langendorff-perfused Scn5a+/- and WT mouse hearts. EpC was reduced with perfusion of a hyponatremic solution, the clinically relevant osmotic agent mannitol, or a combination of the two. Neither in vivo QRS duration nor ex vivo CV during normonatremia was significantly different between the two genotypes. In agreement with our hypothesis, we found that hyponatremia severely slowed CV and disrupted conduction for 4/5 Scn5a+/- mice, but 0/6 WT mice. In addition, treatment with mannitol slowed CV to a greater extent in Scn5a+/- relative to WT hearts. Unexpectedly, treatment with mannitol during hyponatremia did not further slow CV in either genotype, but resolved the disrupted conduction observed in Scn5a+/- hearts. Similar results in guinea pig hearts suggest the effects of mannitol and hyponatremia are not species specific. In conclusion, loss of EpC through either hyponatremia or mannitol alone results in slowed or disrupted conduction in a genetic model of Nav1.5 LOF. However, the combination of these interventions attenuates conduction slowing.NEW & NOTEWORTHY Cardiac sodium channel loss of function (LOF) diseases such as Brugada syndrome (BrS) are often concealed. We optically mapped mouse hearts with reduced sodium channel expression (Scn5a+/-) to evaluate whether reduced ephaptic coupling (EpC) can unmask conduction deficits. Data suggest that conduction deficits in the Scn5a+/- mouse may be unmasked by treatment with hyponatremia and perinexal widening via mannitol. These data support further investigation of hyponatremia and mannitol as novel diagnostics for sodium channel loss of function diseases.


Asunto(s)
Síndrome de Brugada , Hiponatremia , Ratones , Animales , Cobayas , Síndrome de Brugada/genética , Hiponatremia/genética , Corazón , Ventrículos Cardíacos , Canales de Sodio , Canal de Sodio Activado por Voltaje NAV1.5/genética , Potenciales de Acción
4.
Diabetes Obes Metab ; 26(6): 2412-2421, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38558508

RESUMEN

AIM: To evaluate the equivalence of immunogenicity, safety and efficacy of Gan & Lee (GL) Glargine (Basalin®; Gan & Lee Pharmaceutical) with that of the reference product (Lantus®) in adult participants with type 2 diabetes mellitus. METHODS: This was a phase 3, multicenter, open-label, equivalence trial conducted across 57 sites. In total, 567 participants with type 2 diabetes mellitus were randomized in a 1:1 ratio to undergo treatment with either GL Glargine or Lantus® for 26 weeks. The primary endpoint was the proportion of participants in each treatment arm who manifested treatment-induced anti-insulin antibodies (AIA). Secondary endpoints included efficacy and safety metrics, changes in glycated haemoglobin levels, and a comparative assessment of adverse events. Results were analysed using an equivalence test comparing the limits of the 90% confidence interval (CI) for treatment-induced AIA development to the prespecified margins. RESULTS: The percentages of participants positive for treatment-induced glycated haemoglobin by week 26 were similar between the GL Glargine (19.2%) and Lantus® (21.3%) treatment groups, with a treatment difference of -2.1 percentage points and a 90% CI (-7.6%, 3.5%) (predefined similarity margins: -10.7%, 10.7%). The difference in glycated haemoglobin was -0.08% (90% CI, -0.23, 0.06). The overall percentage of participants with any treatment-emergent adverse events was similar between the GL Glargine (80.1%) and Lantus® (81.6%) treatment groups. CONCLUSIONS: GL Glargine was similar to Lantus® in terms of immunogenicity, efficacy, and safety, based on the current study.


Asunto(s)
Biosimilares Farmacéuticos , Diabetes Mellitus Tipo 2 , Hemoglobina Glucada , Hipoglucemiantes , Insulina Glargina , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Biosimilares Farmacéuticos/uso terapéutico , Biosimilares Farmacéuticos/efectos adversos , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/inmunología , Hemoglobina Glucada/efectos de los fármacos , Hemoglobina Glucada/metabolismo , Hemoglobina Glucada/análisis , Hipoglucemia/inducido químicamente , Hipoglucemiantes/uso terapéutico , Hipoglucemiantes/efectos adversos , Anticuerpos Insulínicos/sangre , Insulina Glargina/uso terapéutico , Insulina Glargina/efectos adversos , Equivalencia Terapéutica , Resultado del Tratamiento
5.
J Pathol ; 259(1): 81-92, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36287571

RESUMEN

Cancer of unknown primary (CUP) is a syndrome defined by clinical absence of a primary cancer after standardised investigations. Gene expression profiling (GEP) and DNA sequencing have been used to predict primary tissue of origin (TOO) in CUP and find molecularly guided treatments; however, a detailed comparison of the diagnostic yield from these two tests has not been described. Here, we compared the diagnostic utility of RNA and DNA tests in 215 CUP patients (82% received both tests) in a prospective Australian study. Based on retrospective assessment of clinicopathological data, 77% (166/215) of CUPs had insufficient evidence to support TOO diagnosis (clinicopathology unresolved). The remainder had either a latent primary diagnosis (10%) or clinicopathological evidence to support a likely TOO diagnosis (13%) (clinicopathology resolved). We applied a microarray (CUPGuide) or custom NanoString 18-class GEP test to 191 CUPs with an accuracy of 91.5% in known metastatic cancers for high-medium confidence predictions. Classification performance was similar in clinicopathology-resolved CUPs - 80% had high-medium predictions and 94% were concordant with pathology. Notably, only 56% of the clinicopathology-unresolved CUPs had high-medium confidence GEP predictions. Diagnostic DNA features were interrogated in 201 CUP tumours guided by the cancer type specificity of mutations observed across 22 cancer types from the AACR Project GENIE database (77,058 tumours) as well as mutational signatures (e.g. smoking). Among the clinicopathology-unresolved CUPs, mutations and mutational signatures provided additional diagnostic evidence in 31% of cases. GEP classification was useful in only 13% of cases and oncoviral detection in 4%. Among CUPs where genomics informed TOO, lung and biliary cancers were the most frequently identified types, while kidney tumours were another identifiable subset. In conclusion, DNA and RNA profiling supported an unconfirmed TOO diagnosis in one-third of CUPs otherwise unresolved by clinicopathology assessment alone. DNA mutation profiling was the more diagnostically informative assay. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Asunto(s)
Neoplasias Primarias Desconocidas , Humanos , Neoplasias Primarias Desconocidas/diagnóstico , Neoplasias Primarias Desconocidas/genética , Neoplasias Primarias Desconocidas/patología , Estudios Prospectivos , Estudios Retrospectivos , Australia , Perfilación de la Expresión Génica , Análisis de Secuencia de ADN , ARN
6.
Endocr Pract ; 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38876181

RESUMEN

OBJECTIVE: To compare the immunogenicity, safety, and efficacy of Gan & Lee insulin glargine (GL Glargine) with that of the originator insulin glargine (Lantus) in patients with type 1 diabetes mellitus (T1DM). METHODS: This was a phase 3, multicenter, randomized, open-label, equivalence study. Five hundred seventy-six subjects with T1DM were randomized 1:1 to receive either GL Glargine or Lantus treatment for 26 weeks. The primary end point was the percentage of subjects in each treatment group who developed treatment-induced anti-insulin antibody after baseline and up to visit week 26, which was evaluated using a country-adjusted logistic regression model. The study also compared the changes in glycated hemoglobin, and adverse events including hypoglycemia. RESULTS: The percentage of subjects positive for treatment-induced anti-insulin antibody by Week 26 was 25.8% in the GL Glargine treatment group and 25.3% in the Lantus treatment group, with a 90% confidence interval (-5.4, 6.5) of the difference in proportions that fell completely between the similarity margins (-11.3, 11.3). The least squares mean difference between treatment groups for changes in glycated hemoglobin was -0.08 (90% confidence interval: -0.23, 0.06), and the other immunogenicity and safety profiles were comparable. CONCLUSION: GL Glargine demonstrated similar immunogenicity, efficacy, and safety compared to Lantus over 26 weeks in patients with T1DM.

7.
J Appl Clin Med Phys ; 25(4): e14262, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38234116

RESUMEN

PURPOSE: To investigate whether a novel signal derived from tumor motion allows more precise sorting of 4D-magnetic resonance (4D-MR) image data than do signals based on normal anatomy, reducing levels of stitching artifacts within sorted lung tumor volumes. METHODS: (4D-MRI) scans were collected for 10 lung cancer patients using a 2D T2-weighted single-shot turbo spin echo sequence, obtaining 25 repeat frames per image slice. For each slice, a tumor-motion signal was generated using the first principal component of movement in the tumor neighborhood (TumorPC1). Signals were also generated from displacements of the diaphragm (DIA) and upper and lower chest wall (UCW/LCW) and from slice body area changes (BA). Pearson r coefficients of correlations between observed tumor movement and respiratory signals were determined. TumorPC1, DIA, and UCW signals were used to compile image stacks showing each patient's tumor volume in a respiratory phase. Unsorted image stacks were also built for comparison. For each image stack, the presence of stitching artifacts was assessed by measuring the roughness of the compiled tumor surface according to a roughness metric (Rg). Statistical differences in weighted means of Rg between any two signals were determined using an exact permutation test. RESULTS: The TumorPC1 signal was most strongly correlated with superior-inferior tumor motion, and had significantly higher Pearson r values (median 0.86) than those determined for correlations of UCW, LCW, and BA with superior-inferior tumor motion (p < 0.05). Weighted means of ratios of Rg values in TumorPC1 image stacks to those in unsorted, UCW, and DIA stacks were 0.67, 0.69, and 0.71, all significantly favoring TumorPC1 (p = 0.02-0.05). For other pairs of signals, weighted mean ratios did not differ significantly from one. CONCLUSION: Tumor volumes were smoother in 3D image stacks compiled using the first principal component of tumor motion than in stacks compiled with signals based on normal anatomy.


Asunto(s)
Artefactos , Neoplasias Pulmonares , Humanos , Carga Tumoral , Neoplasias Pulmonares/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Pulmón , Respiración
8.
Angew Chem Int Ed Engl ; 63(20): e202401552, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38497693

RESUMEN

The switching behavior of the novel hybrid material (FA)Na[Fe(CN)5(NO)].H2O (1) in response to temperature (T), light irradiation and electric field (E) is studied using in situ X-ray diffraction (XRD). Crystals of 1 display piezoelectricity, pyroelectricity, second and third harmonic generation. XRD shows that the FA+ are disordered at room-temperature, but stepwise cooling from 273-100 K induces gradual ordering, while cooling under an applied field (E=+40 kVcm-1) induces a sudden phase change at 140 K. Structural-dynamics calculations suggest the field pushes the system into a region of the structural potential-energy surface that is otherwise inaccessible, demonstrating that application of T and E offers an effective route to manipulating the crystal chemistry of these materials. Photocrystallography also reveals photoinduced linkage isomerism, which coexists with but is not correlated to other switching behaviors. These experiments highlight a new approach to in situ studies of hybrid materials, providing insight into the structure-property relationships that underpin their functionality.

9.
N Engl J Med ; 381(9): 841-851, 2019 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-31185157

RESUMEN

BACKGROUND: Establishing cardiovascular safety of new therapies for type 2 diabetes is important. Safety data are available for the subcutaneous form of the glucagon-like peptide-1 receptor agonist semaglutide but are needed for oral semaglutide. METHODS: We assessed cardiovascular outcomes of once-daily oral semaglutide in an event-driven, randomized, double-blind, placebo-controlled trial involving patients at high cardiovascular risk (age of ≥50 years with established cardiovascular or chronic kidney disease, or age of ≥60 years with cardiovascular risk factors only). The primary outcome in a time-to-event analysis was the first occurrence of a major adverse cardiovascular event (death from cardiovascular causes, nonfatal myocardial infarction, or nonfatal stroke). The trial was designed to rule out 80% excess cardiovascular risk as compared with placebo (noninferiority margin of 1.8 for the upper boundary of the 95% confidence interval for the hazard ratio for the primary outcome). RESULTS: A total of 3183 patients were randomly assigned to receive oral semaglutide or placebo. The mean age of the patients was 66 years; 2695 patients (84.7%) were 50 years of age or older and had cardiovascular or chronic kidney disease. The median time in the trial was 15.9 months. Major adverse cardiovascular events occurred in 61 of 1591 patients (3.8%) in the oral semaglutide group and 76 of 1592 (4.8%) in the placebo group (hazard ratio, 0.79; 95% confidence interval [CI], 0.57 to 1.11; P<0.001 for noninferiority). Results for components of the primary outcome were as follows: death from cardiovascular causes, 15 of 1591 patients (0.9%) in the oral semaglutide group and 30 of 1592 (1.9%) in the placebo group (hazard ratio, 0.49; 95% CI, 0.27 to 0.92); nonfatal myocardial infarction, 37 of 1591 patients (2.3%) and 31 of 1592 (1.9%), respectively (hazard ratio, 1.18; 95% CI, 0.73 to 1.90); and nonfatal stroke, 12 of 1591 patients (0.8%) and 16 of 1592 (1.0%), respectively (hazard ratio, 0.74; 95% CI, 0.35 to 1.57). Death from any cause occurred in 23 of 1591 patients (1.4%) in the oral semaglutide group and 45 of 1592 (2.8%) in the placebo group (hazard ratio, 0.51; 95% CI, 0.31 to 0.84). Gastrointestinal adverse events leading to discontinuation of oral semaglutide or placebo were more common with oral semaglutide. CONCLUSIONS: In this trial involving patients with type 2 diabetes, the cardiovascular risk profile of oral semaglutide was not inferior to that of placebo. (Funded by Novo Nordisk; PIONEER 6 ClinicalTrials.gov number, NCT02692716.).


Asunto(s)
Enfermedades Cardiovasculares/inducido químicamente , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Receptor del Péptido 1 Similar al Glucagón/agonistas , Péptidos Similares al Glucagón/administración & dosificación , Hipoglucemiantes/administración & dosificación , Administración Oral , Anciano , Diabetes Mellitus Tipo 2/complicaciones , Método Doble Ciego , Femenino , Péptidos Similares al Glucagón/efectos adversos , Hemoglobina Glucada/análisis , Humanos , Hipoglucemiantes/efectos adversos , Masculino , Persona de Mediana Edad , Riesgo
10.
Nature ; 596(7873): 493-494, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34349273

Asunto(s)
Democracia , Política
11.
Support Care Cancer ; 30(10): 8217-8229, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35804177

RESUMEN

OBJECTIVE: This study aimed to determine the healthcare experiences, quality of life, and psychosocial needs of patients with cancer of unknown primary (CUP) early after diagnosis; comparing their experiences to patients with advanced cancer of a known primary (non-CUP control patients) and published general population reference data where available. METHODS: This study was a cross-sectional, multi-site study comparing CUP patients (n = 139) compared to non-CUP controls (n = 45). Demographic, clinical information and patient-reported outcome questionnaire data were collected at baseline. RESULTS: Differences in healthcare experienced were found between CUP and non-CUP controls with CUP patients reporting higher scores for unmet medical communication/information needs compared with non-CUP control patients (p = 0.013) as well as greater uncertainty in illness (p = 0.042). Whilst no differences were found between CUP and non-CUP controls on the EORTC and PROMIS measures, of those that 'received written information about your cancer…' and asked '…how useful was it?' fewer CUP patients reported finding the information useful 40% vs 61%, and more were likely to not have received written information at all 59% vs 32%; (p = 0.002). Additionally, of those that found information about their cancer online, fewer patients with CUP reported finding it useful 32% vs 48% control patients (p = 0.005). CONCLUSIONS: CUP patients have unmet medical communication/information needs and greater uncertainty in illness but do not differ in health-related quality of life domains compared to patients with advanced cancer of a known primary.


Asunto(s)
Neoplasias Primarias Desconocidas , Calidad de Vida , Estudios Transversales , Necesidades y Demandas de Servicios de Salud , Humanos , Neoplasias Primarias Desconocidas/psicología , Calidad de Vida/psicología , Encuestas y Cuestionarios , Incertidumbre
12.
J Am Chem Soc ; 143(13): 5106-5120, 2021 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-33769815

RESUMEN

Using solid-state molecular organometallic (SMOM) techniques, in particular solid/gas single-crystal to single-crystal reactivity, a series of σ-alkane complexes of the general formula [Rh(Cy2PCH2CH2PCy2)(ηn:ηm-alkane)][BArF4] have been prepared (alkane = propane, 2-methylbutane, hexane, 3-methylpentane; ArF = 3,5-(CF3)2C6H3). These new complexes have been characterized using single crystal X-ray diffraction, solid-state NMR spectroscopy and DFT computational techniques and present a variety of Rh(I)···H-C binding motifs at the metal coordination site: 1,2-η2:η2 (2-methylbutane), 1,3-η2:η2 (propane), 2,4-η2:η2 (hexane), and 1,4-η1:η2 (3-methylpentane). For the linear alkanes propane and hexane, some additional Rh(I)···H-C interactions with the geminal C-H bonds are also evident. The stability of these complexes with respect to alkane loss in the solid state varies with the identity of the alkane: from propane that decomposes rapidly at 295 K to 2-methylbutane that is stable and instead undergoes an acceptorless dehydrogenation to form a bound alkene complex. In each case the alkane sits in a binding pocket defined by the {Rh(Cy2PCH2CH2PCy2)}+ fragment and the surrounding array of [BArF4]- anions. For the propane complex, a small alkane binding energy, driven in part by a lack of stabilizing short contacts with the surrounding anions, correlates with the fleeting stability of this species. 2-Methylbutane forms more short contacts within the binding pocket, and as a result the complex is considerably more stable. However, the complex of the larger 3-methylpentane ligand shows lower stability. Empirically, there therefore appears to be an optimal fit between the size and shape of the alkane and overall stability. Such observations are related to guest/host interactions in solution supramolecular chemistry and the holistic role of 1°, 2°, and 3° environments in metalloenzymes.

13.
Chemistry ; 27(33): 8537-8546, 2021 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-33783895

RESUMEN

The size of single crystals of the metal-organic framework CPO-27-Ni was incrementally increased through a series of modulated syntheses. A novel linker modulated synthesis using 2,5-dihydroxyterephthalic acid and the isomeric ligand 4,6-dihydroxyisophthalic acid yielded large single crystals of CPO-27-Ni (∼70 µm). All materials were shown to have high crystallinity and phase purity through powder X-ray diffraction, electron microscopy methods, thermogravimetry, and compositional analysis. For the first time single-crystal structure analyses were carried out on CPO-27-Ni. High BET surface areas and nitric oxide (NO) release efficiencies were recorded for all materials. Large single crystals of CPO-27-Ni showed a prolonged NO release and proved suitable for in situ single-crystal diffraction experiments to follow the NO adsorption. An efficient activation protocol was developed, leading to a dehydrated structure after just 4 h, which subsequently was NO-loaded, leading to a first NO loaded single-crystal structural model of CPO-27-Ni.

14.
Faraday Discuss ; 225: 133-151, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33179673

RESUMEN

The metal-organic framework (Me2NH2)2[Cd(NO2BDC)2] (SHF-81) comprises flattened tetrahedral Cd(O2CR)42- nodes, in which Cd(ii) centres are linked via NO2BDC2- ligands (2-nitrobenzene-1,4-dicarboxylate) to give a doubly interpenetrated anionic network, with charge balanced by two Me2NH2+ cations per Cd centre resident in the pores. The study establishes that this is a twinned α-quartz-type structure (trigonal, space group P3x21, x = 1 or 2), although very close to the higher symmetry ß-quartz arrangement (hexagonal, P6x22, x = 2 or 4) in its as-synthesised solvated form [Cd(NO2BDC)2]·2DMF·0.5H2O (SHF-81-DMF). The activated MOF exhibits very little N2 uptake at 77 K, but shows significant CO2 uptake at 273-298 K with an isosteric enthalpy of adsorption (ΔHads) at zero coverage of -27.4 kJ mol-1 determined for the MOF directly activated from SHF-81-DMF. A series of in situ diffraction experiments, both single-crystal X-ray diffraction (SCXRD) and powder X-ray diffraction (PXRD), reveal that the MOF is flexible and exhibits breathing behaviour with observed changes as large as 12% in the a- and b-axes (|Δa|, |Δb| < 1.8 Å) and 5.5% in the c-axis (|Δc| < 0.7 Å). Both the solvated SHF-81-DMF and activated/desolvated SHF-81 forms of the MOF exhibit linear negative thermal expansion (NTE), in which pores that run parallel to the c-axis expand in diameter (a- and b-axis) while contracting in length (c-axis) upon increasing temperature. Adsorption of CO2 gas at 298 K also results in linear negative expansion (Δa, Δb > 0; Δc < 0; ΔV > 0). The largest change in dimensions is observed during activation/desolvation from SHF-81-DMF to SHF-81 (Δa, Δb < 0; Δc > 0; ΔV < 0). Collectively the nine in situ diffraction experiments conducted suggest the breathing behaviour is continuous, although individual desolvation and adsorption experiments do not rule out the possibility of a gating or step at intermediate geometries that is coupled with continuous dynamic behaviour towards the extremities of the breathing amplitude.

15.
Diabetes Obes Metab ; 23(7): 1552-1561, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33687783

RESUMEN

AIM: To evaluate the efficacy and safety of ultra rapid lispro (URLi) versus lispro (Humalog® ) in people with type 1 diabetes on continuous subcutaneous insulin infusion (CSII). MATERIALS AND METHODS: This was a phase 3, 16-week, treat-to-target study in patients randomized to double-blind URLi (N = 215) or lispro (N = 217). The primary endpoint was change from baseline HbA1c (non-inferiority margin 4.4 mmol/mol [0.4%]), with multiplicity-adjusted objectives for postprandial glucose (PPG) levels during a meal test, and time spent in the target range 70-180 mg/dL (TIR). RESULTS: URLi was non-inferior to lispro for change in HbA1c, with a least-squares mean (LSM) difference of 0.3 mmol/mol (95% confidence interval [CI] -0.6, 1.2) or 0.02% (95% CI -0.06, 0.11). URLi was superior to lispro in controlling 1- and 2-h PPG levels after the meal test: LSM difference -1.34 mmol/L (95% CI -2.00, -0.68) or -24.1 mg/dL (95% CI -36.0, -12.2) at 1 h and -1.54 mmol/L (95% CI -2.37, -0.72) or -27.8 mg/dL (95% CI -42.6, -13.0) at 2 h; both p < .001. TIR and time in hyperglycaemia were similar between groups but URLi resulted in significantly less time in hypoglycaemia (<3.0 mmol/L [54 mg/dL]) over the daytime, night-time and 24-h period: LSM difference -0.41%, -0.97% and -0.52%, respectively, all p < .05. The incidence of treatment-emergent adverse events was higher with URLi (60.5% vs. 44.7%), driven by infusion-site reaction and infusion-site pain, which was mostly mild or moderate. Rates of severe hypoglycaemia and diabetic ketoacidosis were similar between groups. CONCLUSIONS: URLi was efficacious, providing superior PPG control and less time in hypoglycaemia but with more frequent infusion-site reactions compared with lispro when administered by CSII.


Asunto(s)
Glucemia , Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Hemoglobina Glucada/análisis , Humanos , Hipoglucemiantes/efectos adversos , Insulina , Insulina Lispro
16.
Inorg Chem ; 60(12): 8665-8671, 2021 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-34085813

RESUMEN

The mononuclear cobalt complex of 3,5-di-tert-butylcathecolate and cyan-pyridine (Co(diox)2(4-CN-py)2) is a very versatile compound that displays valence tautomerism (VT) in the solid state, which is induced by temperature, light, and hard X-rays, and modulated by solvent in the crystal lattice. In our work, we used single crystal X-ray diffraction as a probe for the light-induced VT in solid state and demonstrate the controlled use of hard X-rays via attenuation to avoid X-ray-induced VT interconversion. We report photoinduced VT in benzene solvated crystals of Co(diox)2(4-CN-py)2 illuminated with blue 450 nm light at 30 K with a very high yield (80%) of metastable hs-CoII states, and we also show evidence of the de-excitation of these photoinduced metastable states using red 660 nm light. Such high-yield light-induced VT had never been experimentally observed in molecular crystals of cobalt tautomers, proving that the 450 nm light illumination is triggering a chain of events that leads to the ls-CoIII to hs-CoII interconversion.

17.
Remote Sens Environ ; 265: 112651, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34732943

RESUMEN

High resolution imaging spectrometers are prerequisite to address significant data gaps in inland optical water quality monitoring. In this work, we provide a data-driven alignment of chlorophyll-a and turbidity derived from the Sentinel-2 MultiSpectral Imager (MSI) with corresponding Sentinel-3 Ocean and Land Colour Instrument (OLCI) products. For chlorophyll-a retrieval, empirical 'ocean colour' blue-green band ratios and a near infra-red (NIR) band ratio algorithm, as well as a semi-analytical three-band NIR-red ratio algorithm, were included in the analysis. Six million co-registrations with MSI and OLCI spanning 24 lakes across five continents were analysed. Following atmospheric correction with POLYMER, the reflectance distributions of the red and NIR bands showed close similarity between the two sensors, whereas the distribution for blue and green bands was positively skewed in the MSI results compared to OLCI. Whilst it is not possible from this analysis to determine the accuracy of reflectance retrieved with either MSI or OLCI results, optimizing water quality algorithms for MSI against those previously derived for the Envisat Medium Resolution Imaging Spectrometer (MERIS) and its follow-on OLCI, supports the wider use of MSI for aquatic applications. Chlorophyll-a algorithms were thus tuned for MSI against concurrent OLCI observations, resulting in significant improvements against the original algorithm coefficients. The mean absolute difference (MAD) for the blue-green band ratio algorithm decreased from 1.95 mg m-3 to 1.11 mg m-3, whilst the correlation coefficient increased from 0.61 to 0.80. For the NIR-red band ratio algorithms improvements were modest, with the MAD decreasing from 4.68 to 4.64 mg m-3 for the empirical red band ratio algorithm, and 3.73 to 3.67 for the semi-analytical 3-band algorithm. Three implementations of the turbidity algorithm showed improvement after tuning with the resulting distributions having reduced bias. The MAD reduced from 0.85 to 0.72, 1.22 to 1.10 and 1.93 to 1.55 FNU for the 665, 708 and 778 nm implementations respectively. However, several sources of uncertainty remain: adjacent land showed high divergence between the sensors, suggesting that high product uncertainty near land continues to be an issue for small water bodies, while it cannot be stated at this point whether MSI or OLCI results are differentially affected. The effect of spectrally wider bands of the MSI on algorithm sensitivity to chlorophyll-a and turbidity cannot be fully established without further availability of in situ optical measurements.

18.
Plant Dis ; 2021 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-34420364

RESUMEN

Watermelon (Citrullus lanatus) is a high nutrient crop, high in vitamins and very popular in the U.S and globally. The crop was harvested from 101,800 acres with a value of $560 million in the U.S (USDA-NASS, 2020). California, Florida, Georgia and Texas are the four-leading watermelon-producing states in the U.S. During the fall season of 2020, plants in two North Florida watermelon fields, one in Levy County (~20 acres) and one in Suwannee County (~80 acres) with varieties Talca and Troubadour, respectively, exhibited viral-like symptoms. The fields had 100% disease incidence that led to fruit quality issues and yield losses of 80% and above. Symptoms observed in the watermelon samples included leaf crumpling, yellowing and curling, and vein yellowing similar to that of single/and or mixed infection of cucurbit leaf crumple virus (CuLCrV; genus: Begomovirus, family: Geminiviridae), cucurbit yellow stunting disorder virus (CYSDV; genus: Crinivirus, family: Closteroviridae) and squash vein yellowing virus (SqVYV; genus: Ipomovirus, family: Potyviridae), although the vine decline symptoms often associated with SqVYV infection of watermelon were not observed. All three viruses are vectored by whiteflies and previously described in Florida (Akad et al., 2008; Polston et al., 2008; Adkins et al., 2009). To confirm the presence of these viruses, RNA was isolated from 20 symptomatic samples using the RNeasy Plant Mini Kit (Qiagen, USA) as per protocol. This was followed by RT-PCR (NEB, USA) using gene-specific primers described for CuLCrV, CYSDV and SqVYV (Adkins et al., 2009). Amplicons of expected sizes were obtained for all the viruses with the infection of CuLCrV in 17/20, CYSDV in 16/20, and SqVYV in 8/20 samples. In addition, the presence of cucurbit chlorotic yellows virus (CCYV; genus: Crinivirus, family: Closteroviridae) in mixed infection was confirmed in 4/20 samples (3 leaves and 1 fruit) by RT-PCR with primers specific to the CCYV coat protein (CP), heat shock protein 70 homolog (HSP70h) and RNA dependent RNA polymerase (RdRp) designed based on the available CCYV sequences (Sup Table. 1). The RT-PCR amplification was performed using a symptomatic watermelon sample and the amplicons of RdRp, HSP70h and CP were directly sequenced by Sanger method, and the sequences of the amplicons were deposited in GenBank under the accession number: MW527462 (RdRp, 952 bp), MW527461 (HSP70h, 583 bp) and MW527460 (CP, 852 bp). BLASTn analysis demonstrated that the sequences exhibited an identity of 99% to 100% (RdRp and HSP70h, 100%; and CP, 99%) with the corresponding regions of the CCYV isolate Shanghai from China (accession number: KY400636 and KY400633). The presence of CCYV was further confirmed in the watermelon samples by ELISA (Loewe, Germany) using crude sap extracted from the RT-PCR-positive, symptomatic watermelon samples. CCYV was first identified in Kumamoto, Japan in 2004 on melon plants (Gyoutoku et al. 2009). The CCYV was previously reported on melon from Imperial Valley, California (Wintermantel et al., 2019), and more recently on squash in Tifton, Georgia (Kavalappara et al., 2021) and cantaloupe in Cameron, Texas (Hernandez et al., 2021). To our knowledge, this is the first report of CCYV on field watermelon production in the U.S. Continued monitoring of the CCYV in spring and fall watermelon crop, and cucurbit volunteers and weeds will be critical toward understanding the spread of this virus and its potential risk to watermelon in Florida and other regions of the U.S.

19.
Angew Chem Int Ed Engl ; 60(33): 17920-17924, 2021 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-34062045

RESUMEN

Post-synthetic modification (PSM) of the interpenetrated diamondoid metal-organic framework (Me2 NH2 )[In(BDC-NH2 )2 ] (BDC-NH2 =aminobenzenedicarboxylate) SHF-61 proceeds quantitatively in a single-crystal-to-single-crystal manner to yield the acetamide derivative (Me2 NH2 )[In(BDC-NHC(O)Me)2 ] SHF-62. Continuous breathing behaviour during activation/desolvation is retained upon PSM, but pore closing now leads to ring-flipping to avert steric clash of amide methyl groups of the modified ligands. This triggers a reduction in the amplitude of the breathing deformation in the two dimensions associated with pore diameter, but a large increase in the third dimension associated with pore length. The MOF is thereby converted from predominantly 2D breathing (in SHF-61) to a distinctly 3D breathing motion (in SHF-62) indicating a decoupling of the pore-width and pore-length breathing motions. These breathing motions have been mapped by a series of single-crystal diffraction studies.

20.
J Am Chem Soc ; 142(47): 20088-20097, 2020 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-33172264

RESUMEN

Flexible metal-organic frameworks (MOFs) hold great promise as smart materials for specific applications such as gas separation. These materials undergo interesting structural changes in response to guest molecules, which is often associated with unique adsorption behavior not possible for rigid MOFs. Understanding the dynamic behavior of flexible MOFs is crucial yet challenging as it involves weak host-guest interactions and subtle structural transformation not only at the atomic/molecular level but also in a nonsteady state. We report here an in-depth study on the adsorbate- and temperature-dependent adsorption in a flexible MOF by crystallizing atomic gases into its pores. Mn(ina)2 shows an interesting temperature-dependent response toward noble gases. Its nonmonotonic, temperature-dependent adsorption profile results in an uptake maximum at a temperature threshold, a phenomenon that is unusual. Full characterization of Xe-loaded MOF structures is performed by in situ single-crystal and synchrotron X-ray diffraction, IR spectroscopy, and molecular modeling. The X-ray diffraction analysis offers a detailed explanation into the dynamic structural transformation and provides a convincing rationalization of the unique adsorption behavior at the molecular scale. The guest and temperature dependence of the structural breathing gives rise to an intriguing reverse of Xe/Kr adsorption selectivity as a function of temperature. The presented work may provide further understanding of the adsorption behavior of noble gases in flexible MOF structures.

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