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1.
Small ; : e2403028, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38860552

RESUMO

Methane is a valuable resource and its valorization is an important challenge in heterogeneous catalysis. Here it is shown that CeO2/CuO composite prepared by ball milling activates methane at a temperature as low as 250 °C. In contrast to conventionally prepared catalysts, the formation of partial oxidation products such as methanol and formaldehyde is also observed. Through an in situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) and operando Near Edge X-Ray Absorption Fine Structure Spectroscopy (NEXAFS) approach, it can be established that this unusual reactivity can be attributed to the presence of Ce4+/Cu+ interfaces generated through a redox exchange between Ce3+ and Cu2+ atoms facilitated by the mechanical energy supplied during milling. DFT modeling of the electronic properties confirms the existence of a charge transfer mechanism. These results demonstrate the effectiveness and distinctiveness of the mechanical approach in creating unique and resilient interfaces thereby enabling the optimization and refining of CeO2/CuO catalysts in methane activation reactions.

2.
J Exp Bot ; 75(10): 3092-3110, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38387000

RESUMO

Lemnaceae taxonomy is challenged by the particular morphology of these tiny free-floating angiosperms. Although molecular taxonomy has helped clarify the phylogenetic history of this family, some inconsistency with morphological data leads to frequent misclassifications in the genus Lemna. Recently, the finding that Lemna japonica is an interspecific hybrid between Lemna minor and Lemna turionifera provided a clear explanation for one such taxonomic question. Here we demonstrated that L. minor is also capable of hybridizing with Lemna gibba, generating a cryptic but widespread taxon in the Mediterranean area. The nothotaxon Lemna ×mediterranea is described and compared with clones of the putative parental species L. minor and L. gibba. Genetic analysis by nuclear and plastid markers, as well as genome size measurement, revealed that two different cytotypes, diploid and triploid, originated by at least two independent hybridization events. Despite high overall similarity, morphometrical, physiological, and biochemical analyses showed an intermediate position of L. ×mediterranea between its parental species in most qualitative and quantitative characters, and also separation of the two hybrid cytotypes by some criteria. These data provide evidence that hybridization and polyploidization, driving forces of terrestrial plant evolution, contribute to duckweed genetic diversity and may have shaped the phylogenetic history of these mainly asexual, aquatic plants.


Assuntos
Araceae , Hibridização Genética , Filogenia , Araceae/genética , Variação Genética , Poliploidia , Genoma de Planta , Biodiversidade
3.
J Am Chem Soc ; 145(38): 21040-21052, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37721732

RESUMO

Iron-based enzymes efficiently activate molecular oxygen to perform the oxidation of methane to methanol (MTM), a reaction central to the contemporary chemical industry. Conversely, a very limited number of artificial catalysts have been devised to mimic this process. Herein, we employ the MIL-100(Fe) metal-organic framework (MOF), a material that exhibits isolated Fe sites, to accomplish the MTM conversion using O2 as the oxidant under mild conditions. We apply a diverse set of advanced operando X-ray techniques to unveil how MIL-100(Fe) can act as a catalyst for direct MTM conversion. Single-phase crystallinity and stability of the MOF under reaction conditions (200 or 100 °C, CH4 + O2) are confirmed by X-ray diffraction measurements. X-ray absorption, emission, and resonant inelastic scattering measurements show that thermal treatment above 200 °C generates Fe(II) sites that interact with O2 and CH4 to produce methanol. Experimental evidence-driven density functional theory (DFT) calculations illustrate that the MTM reaction involves the oxidation of the Fe(II) sites to Fe(III) via a high-spin Fe(IV)═O intermediate. Catalyst deactivation is proposed to be caused by the escape of CH3• radicals from the relatively large MOF pore cages, ultimately resulting in the formation of hydroxylated triiron units, as proven by valence-to-core X-ray emission spectroscopy. The O2-based MTM catalytic activity of MIL-100(Fe) in the investigated conditions is demonstrated for two consecutive reaction cycles, proving the MOF potential toward active site regeneration. These findings will desirably lay the groundwork for the design of improved MOF catalysts for the MTM conversion.

4.
Angew Chem Int Ed Engl ; 62(25): e202302087, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37062698

RESUMO

CO2 hydrogenation to methane is gaining increasing interest as one of the most promising ways to store intermittent renewable energy in the form of chemical fuels. Ni particles supported on CeO2 represent a highly efficient, stable and inexpensive catalyst for this reaction. Herein, Ni-doped CeO2 nanoparticles were tested for CO2 methanation showing an extremely high Ni mass-specific activity and CH4 selectivity. Operando characterization reveals that this performance is tightly associated with ionic Νi and Ce3+ surface sites, while formation of metallic Ni does not seem to considerably promote the reaction. Theoretical calculations confirmed the stability of interstitial ionic Ni sites on ceria surfaces and highlighted the role of Ce-O frustrated Lewis pair (FLP), Ni-O classical Lewis pair (CLP) and Ni-Ce pair sites to the activation of H2 and CO2 molecules. To a large extent, the theoretical predictions were validated by in situ spectroscopy under H2 and CO2 : H2 gaseous environments.


Assuntos
Dióxido de Carbono , Níquel , Gases , Hidrogenação , Íons
5.
Cancer ; 128(1): 85-93, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34643947

RESUMO

BACKGROUND: The value of neoadjuvant chemotherapy in soft tissue sarcoma (STS) is not completely understood. This study investigated the benefit of neoadjuvant chemotherapy according to prognostic stratification based on the Sarculator nomogram for STS. METHODS: This study analyzed data from ISG-STS 1001, a randomized study that tested 3 cycles of neoadjuvant anthracycline plus ifosfamide (AI) or histology-tailored (HT) chemotherapy in adult patients with STS. The 10-year predicted overall survival (pr-OS) was estimated with the Sarculator and was stratified into higher (10-year pr-OS < 60%) and lower risk subgroups (10-year pr-OS ≥ 60%). RESULTS: The median pr-OS was 0.63 (interquartile range [IQR], 0.51-0.72) for the entire study population, 0.62 (IQR, 0.51-0.70) for the AI arm, and 0.64 (IQR, 0.51-0.73) for the HT arm. Three- and 5-year overall survival (OS) were 0.86 (95% confidence interval [CI], 0.82-0.93) and 0.81 (95% CI, 0.71-0.86) in lower risk patients and 0.69 (95% CI, 0.70-0.85) and 0.59 (95% CI, 0.51-0.72) in the higher risk patients (log-rank test, P = .004). In higher risk patients, the 3- and 5-year Sarculator-predicted and study-observed OS rates were 0.68 and 0.58, respectively, and 0.85 and 0.66, respectively, in the AI arm (P = .04); the corresponding figures in the HT arm were 0.69 and 0.60, respectively, and 0.69 and 0.55, respectively (P > .99). In lower risk patients, the 3- and 5-year Sarculator-predicted and study-observed OS rates were 0.85 and 0.80, respectively, and 0.89 and 0.82, respectively, in the AI arm (P = .507); the corresponding figures in the HT arm were 0.87 and 0.81, respectively, and 0.86 and 0.74, respectively (P = .105). CONCLUSIONS: High-risk patients treated with AI performed better than predicted, and this adds to the evidence for the efficacy of neoadjuvant AI in STS. LAY SUMMARY: People affected by soft tissue sarcomas of the extremities and trunk wall are at some risk of developing metastasis after surgery. Preoperative or postoperative chemotherapy has been tested in clinical trials to reduce the chances of distant metastasis. However, study findings have not been conclusive. This study stratified the risk of metastasis for people affected by sarcomas who were included in a clinical trial testing neoadjuvant chemotherapy. Exploiting the prognostic nomogram Sarculator, it found a benefit for chemotherapy when the predicted risk, based on patient and tumor characteristics, was high.


Assuntos
Sarcoma , Neoplasias de Tecidos Moles , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioterapia Adjuvante , Humanos , Ifosfamida , Terapia Neoadjuvante , Medição de Risco , Sarcoma/patologia
6.
Phys Chem Chem Phys ; 23(46): 26575-26584, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34812450

RESUMO

High entropy oxides (HEOs) are an emerging class of materials constituted by multicomponent systems that are receiving special interest as candidates for obtaining novel and desirable properties. In this study we present a detailed investigation of the relevant intermediates arising at the surface of the prototypical HEO Mg0.2Co0.2Ni0.2Cu0.2Zn0.2O during low-temperature CO oxidation. By combining Cu L2,3-edge operando soft X-ray absorption spectroscopy (soft-XAS) with density functional theory simulations and in situ FT-IR spectroscopy, we propose that upon HEO exposure to CO at 235 °C reduced Cu(I) sites arise mostly coordinated to activated CO molecules and partly to bidentate carbonate species. When the HEO surface is then exposed to a stoichiometric mixture of CO + 1/2O2 at 250 °C, CO2 is produced while bidentate carbonate moieties remain interacting with the Cu(I) sites. We structurally characterize the carbonate and CO preferential adsorption geometries on the Cu(I) surface metal centers, and find that CO adopts a bent conformation that may energetically favor its subsequent oxidation. The unique surface, structural and electronic sensitivity of soft-XAS coupled with the developed data analysis work-flow and supported by FT-IR spectroscopy may be beneficial to characterize often elusive surface properties of systems of catalytic interest.

7.
BMC Palliat Care ; 20(1): 129, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34399737

RESUMO

BACKGROUND: Dignity is a basic principle of palliative care and is intrinsic in the daily practice of professionals assisting individuals with incurable diseases. Dignity Therapy (DT) is a short-term intervention aimed at improving the sense of purpose, meaning and self-worth and at reducing the existential distress of patients facing advanced illness. Few studies have examined how DT works in countries of non-Anglo Saxon culture and in different real-life settings. Moreover, most studies do not provide detailed information on how DT is conducted, limiting a reliable assessment of DT protocol application and of its evaluation procedure. The aim of this study was to assess the feasibility and acceptability of a nurse-led DT intervention in advanced cancer patients receiving palliative care. METHOD: This is a mixed-method study using before and after evaluation and semistructured interviews. Cancer patients referred to a hospital palliative care unit were recruited and provided with DT. The duration of sessions, and timeframes concerning each step of the study, were recorded, and descriptive statistical analyses were performed. The patients' dignity-related distress and feedback toward the intervention were assessed through the Patient Dignity Inventory and the Dignity Therapy Patient Feedback Questionnaire, respectively. Three nurses were interviewed on their experience in delivering the intervention, and the data were analyzed qualitatively. RESULTS: A total of 37/50 patients were enrolled (74.0%), of whom 28 (75.7%) completed the assessment. In 76.7% of cases, patients completed the intervention in the time limit scheduled in the study. No statistically significant reduction in the Patient Dignity Inventory scores was observed at the end of the intervention; most patients found DT to be helpful and satisfactory. Building opportunities for personal growth and providing holistic care emerged among the facilitators to DT implementation. Nurses also highlighted too great of a time commitment and a difficult collaboration with ward colleagues among the barriers. CONCLUSIONS: Our findings strongly support the acceptability, but only partially support the feasibility, of nurse-led DT in advanced cancer patients in a hospital setting. Further research is needed on how to transfer the potential benefits of DT into clinical practice. TRIAL REGISTRATION: Retrospectively registered on ClinicalTrial.gov NCT04738305 .


Assuntos
Neoplasias , Assistência Terminal , Estudos de Viabilidade , Hospitais , Humanos , Neoplasias/terapia , Cuidados Paliativos , Respeito
8.
J Synchrotron Radiat ; 27(Pt 6): 1741-1752, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33147203

RESUMO

THORONDOR is a data treatment software with a graphical user interface (GUI) accessible via the browser-based Jupyter notebook framework. It aims to provide an interactive and user-friendly tool for the analysis of NEXAFS spectra collected during in situ experiments. The program allows on-the-fly representation and quick correction of large datasets from single or multiple experiments. In particular, it provides the possibility to align in energy several spectral profiles on the basis of user-defined references. Various techniques to calculate background subtraction and signal normalization have been made available. In this context, an innovation of this GUI involves the usage of a slider-based approach that provides the ability to instantly manipulate and visualize processed data for the user. Finally, the program is characterized by an advanced fitting toolbox based on the lmfit package. It offers a large selection of fitting routines as well as different peak distributions and empirical ionization potential step edges, which can be used for the fit of the NEXAFS rising-edge peaks. Statistical parameters describing the goodness of a fit such as χ2 or the R-factor together with the parameter uncertainty distributions and the related correlations can be extracted for each chosen model.

9.
Digestion ; 101(2): 144-155, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30783050

RESUMO

BACKGROUND/AIMS: At present, benefits of surgical resection and appropriate selection criteria in patients affected by both hepatic and pulmonary metastases of colorectal cancer (CRC) are under discussion. Our analysis focused on a surgical series of such patients and our final aim consisted in identifying potential prognostic factors. METHODS: Eighty-five patients undergoing resection of both hepatic and pulmonary metastases at 2 Healthcare Institutions from January 1993 to June 2015 were retrospectively reviewed as concerned clinical information, surgical notes and pathological features. Patient, treatment, and outcome variables were analyzed by use of log-rank tests, Cox regression, and Kaplan-Meier methods. RESULTS: Liver turned out as the first site of metastasis in 75% patients, lung in 13% patients, and both sites in 12% patients. Multiple hepatic metastases were detected in 67% patients and pulmonary metastases in 31% patients. Two hundred eighteen surgical interventions were performed (mean 2.56 for each patient). Overall survival (OS) rates at 3-, 5-, and 10-year follow-up from colorectal resection were 94, 79, and 38% respectively. Median OS was 8.31 years. Survival turned out significantly longer for patients with disease-free interval (DFI) exceeding 1 year between first metastasectomy and diagnosis of second metastases and in patients affected by metachronous pulmonary metastases. CONCLUSIONS: Surgical resection of both hepatic and pulmonary metastases of CRC represents a safe and effective treatment. It might lead to rewarding long-term survival rates in high selected patients. Shorter DFIs between first metastasectomy and diagnosis of second metastases can determine worse prognoses. In addition, poor outcomes could be predicted also for patients affected by synchronously detected pulmonary CRC metastases, although further confirmatory analyses are strongly required.


Assuntos
Neoplasias Colorretais/cirurgia , Hepatectomia/mortalidade , Neoplasias Hepáticas/cirurgia , Neoplasias Pulmonares/cirurgia , Neoplasias Primárias Múltiplas/cirurgia , Pneumonectomia/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Feminino , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/secundário , Masculino , Pessoa de Meia-Idade , Neoplasias Primárias Múltiplas/secundário , Seleção de Pacientes , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
10.
Angew Chem Int Ed Engl ; 59(41): 18145-18150, 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-32648335

RESUMO

Ti silicates, and in particular, titanium silicalite-1 (TS-1), are nowadays important catalysts for several partial oxidation reactions in the presence of aqueous H2 O2 as an oxidant. Despite the numerous studies dealing with this material, some fundamental aspects are still unclear. In particular, the structure and the catalytic role of defective Ti sites, other than perfect tetrahedral sites recognized as the main active species, has not been quantitatively discussed in the literature. We assess the structural features of defective Ti sites on the basis of outcomes of electronic spectroscopies, as interpreted through quantum mechanical simulation. Strong evidence is disclosed to support the fact that the most common defective Ti sites, often reported in the TS-1 literature, are monomeric Ti centers that are embedded in the zeolite framework, and which have a distorted octahedral local symmetry.

11.
Reprod Biol Endocrinol ; 17(1): 84, 2019 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-31656205

RESUMO

BACKGROUND: In the absence of international guidelines indicating the usage of vitrification rather than slow-freezing, the study aim was to analyze a large cohort of slow-frozen/thawed embryos to produce a rationale supporting the standardization of IVF cryopreservation policy. METHODS: This retrospective analysis included 4779 cleavage stage embryos cryopreserved by slow-freezing/thawing from September 2009 to April 2017 at a single Center. Biological and clinical outcomes of three different commercial kits adopted sequentially, i.e. Vitrolife Cleave Kit® from Vitrolife (kit 1) vs. K-SICS-5000 Kit® and K-SITS-5000 Kit® from Cook Medical (kit 2) and Freeze/Thaw 1™ Kit® from Vitrolife (kit 3) were collected and compared in the light of cryoprotectants composition. RESULTS: Kit 3 compared to kit 1 and kit 2 showed significantly (P < 0.001) higher embryo survival (79.9% vs. 75.6 and 68.1%, respectively) and frozen embryo replacement (91.5% vs. 86.5 and 83.3%, respectively) rates, and significantly (P < 0.001) lower blastomere degeneration rate (41.5% vs. 43.6 and 52.4%, respectively). No significant difference for clinical outcomes was observed among kits. Only a slight positive trend was observed for kit 3 vs. kit 1 and kit 2 on delivery rate per thawing cycle (7.12% vs. 4.19 and 4.51%, respectively; P < 0.058) and live birth rate (3.07% vs. 2.59 and 1.93%, respectively, P < 0.069). Thawing solutions of kit 3 were similar to those of any warming protocol. CONCLUSIONS: A defined concentration of extracellular cryoprotectants in thawing/warming solutions had a beneficial effect on the embryo cryosurvival rate. Results could provide the rationale for the adoption of a single standardized warming protocol.


Assuntos
Blastômeros/fisiologia , Fase de Clivagem do Zigoto/fisiologia , Criopreservação/métodos , Crioprotetores/farmacologia , Embrião de Mamíferos/fisiologia , Vitrificação/efeitos dos fármacos , Blastômeros/citologia , Transferência Embrionária , Embrião de Mamíferos/citologia , Feminino , Humanos , Gravidez , Taxa de Gravidez , Estudos Retrospectivos
12.
Radiology ; 288(2): 375-385, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29869961

RESUMO

Purpose To compare digital mammography (DM) plus digital breast tomosynthesis (DBT) versus DM alone for breast cancer screening in the Reggio Emilia Tomosynthesis trial, a two-arm test-and-treat randomized controlled trial. Materials and Methods For this trial, eligible women (45-70 years old) who previously participated in the Reggio Emilia screening program were invited for mammography. Consenting women were randomly assigned 1:1 to undergo DBT+DM or DM (both of which involved two projections and double reading). Women were treated according to the decision at DBT+DM. Sensitivity, recall rate, and positive predictive value (PPV) at baseline were determined; the ratios of these rates for DBT+DM relative to DM alone were determined. Results From March 2014 to March 2016, 9777 women were recruited to the DM+DBT arm of the study, and 9783 women were recruited to the DM arm (mean age, 56.2 vs 56.3 years). Recall was 3.5% in both arms; detection was 4.5 per 1000 (44 of 9783) and 8.6 per 1000 (83 of 9777), respectively (+89%; 95% confidence interval [CI]: 31, 72). PPV of the recall was 13.0% and 24.1%, respectively (P = .0002); 72 of 80 cancers found in the DBT+DM arm and with complete DBT imaging were positive at least at one DBT-alone reading. The greater detection rate for DM+DBT was stronger for ductal carcinoma in situ (+180%, 95% CI: 1, 665); it was notable for small and medium invasive cancers, but not for large ones (+94 [95% CI: 6, 254]; +122 [95% CI: 18, 316]; -12 [95% CI: -68, 141]; for invasive cancers < 10 mm, 10-19 mm, and ≥ 20 mm, respectively). Conclusion DBT+DM depicts 90% more cancers in a population previously screened with DM, with similar recall rates.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Detecção Precoce de Câncer/métodos , Mamografia/métodos , Programas de Rastreamento/métodos , Intensificação de Imagem Radiográfica/métodos , Idoso , Mama/diagnóstico por imagem , Feminino , Humanos , Itália , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
13.
J Synchrotron Radiat ; 25(Pt 4): 989-997, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29979160

RESUMO

A setup for fluorescence-detected X-ray absorption spectroscopy (XAS) with sub-second time resolution has been developed. This technique allows chemical speciation of low-concentrated materials embedded in highly absorbing matrices, which cannot be studied using transmission XAS. Using this setup, the reactivity of 1.5 wt% Pt/CeO2 catalyst was studied with 100 ms resolution during periodic cycling in CO- and oxygen-containing atmospheres in a plug-flow reactor. Measurements were performed at the Pt L3- and Ce L3-edges. The reactivity of platinum and cerium demonstrated a strong correlation. The oxidation of the catalyst starts on the ceria support helping the oxidation of platinum nanoparticles. The new time-resolved XAS setup can be applied to various systems, capable of reproducible cycling between different states triggered by gas atmosphere, light, temperature, etc. It opens up new perspectives for mechanistic studies on automotive catalysts, selective oxidation catalysts and photocatalysts.

14.
Faraday Discuss ; 208(0): 287-306, 2018 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-29796547

RESUMO

Functionalization of metal-organic frameworks with metal nanoparticles (NPs) is a promising way for producing advanced materials for catalytic applications. We present the synthesis and in situ characterization of palladium NPs encapsulated inside a functionalized UiO-67 metal-organic framework. The initial structure was synthesized with 10% of PdCl2bpydc moieties with grafted Pd ions replacing standard 4,4'-biphenyldicarboxylate linkers. This material exhibits the same high crystallinity and thermal stability of standard UiO-67. Formation of palladium NPs was initiated by sample activation in hydrogen and monitored by in situ X-ray powder diffraction and X-ray absorption spectroscopy (XAS). The reduction of PdII ions to Pd0 occurs above 200 °C in 6% H2/He flow. The formed palladium NPs have an average size of 2.1 nm as limited by the cavities of UiO-67 structure. The resulting material showed high activity towards ethylene hydrogenation. Under reaction conditions, palladium was found to form a carbide structure indicated by operando XAS, while formation of ethane was monitored by mass spectroscopy and infra-red spectroscopy.

15.
Inorg Chem ; 57(21): 13998-14004, 2018 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-30354088

RESUMO

Although X-ray absorption spectroscopy (XAS) has become an indispensable tool in characterization of solid-state materials, it is less of a staple in molecular chemistry of niobium. Scattering X-ray techniques remain relatively unexplored for the systematic study of molecular niobium compounds. Here, we use XAS to probe the niobium environment in commonly used Nb precursors in +V, +IV, and +III oxidation states. Apart from laying out the guidelines for identification of niobium oxidation states, we correlate our data with density functional theory models to provide further structural insight. Of particular note, we are able to shed light on the nature of the commonly used and catalytically competent NbCl3(DME), which had not been previously characterized structurally despite its prevalence in Nb chemistry.

16.
Intern Med J ; 48(10): 1192-1197, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29740921

RESUMO

BACKGROUND: Adverse drug reaction (ADR) is a leading but under-recognised cause of illness, particularly in frail subjects with multiple comorbidities. AIM: To investigate the frequency, patterns and outcomes of ADR as a cause of hospitalisation in elderly patients admitted to an internal medicine ward. METHODS: We performed a retrospective observational study including every patient aged over 65 years who was admitted to our department during a 12-month period. Patients admitted to short-stay (<24 h) observation unit were excluded. RESULTS: ADR accounted for 106 of total 1750 recorded admissions, which constituted a proportion of 6.1% (95% confidence interval 5.0-7.3%). The median age of patients was 83.5 (78.0-87.0) years and 56.6% were on polypharmacy. A total of 170 ADR was recorded with 45.3% of subjects experiencing concomitantly more than one ADR from a single molecule. Diuretics were the most commonly imputed molecules (30 events, 17.6%), followed by antithrombotics (25 events, 14.7%) and central nervous system-active drugs (16 events, 9.4%). Interactions were judged responsible for 39 cases of ADR (36.8%). An unfavourable outcome was observed in about one-third of patients (37.7%). Among those subjects, 11 (10.4%) died and 29 (27.4%) had residual disability. CONCLUSION: ADR are a common cause of hospital admission in elderly patients and are often associated with adverse outcomes. Our data underline the need of appropriate strategies aimed at identifying high-risk patients and avoiding potentially preventable drug toxicities.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Hospitalização/estatística & dados numéricos , Tempo de Internação/estatística & dados numéricos , Polimedicação , Sistemas de Notificação de Reações Adversas a Medicamentos , Idoso , Idoso de 80 Anos ou mais , Fármacos do Sistema Nervoso Central/efeitos adversos , Comorbidade , Diuréticos/efeitos adversos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/complicações , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/terapia , Feminino , Fibrinolíticos/efeitos adversos , Humanos , Itália/epidemiologia , Masculino , Erros de Medicação/estatística & dados numéricos , Estudos Retrospectivos
17.
J Am Chem Soc ; 139(47): 17064-17073, 2017 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-28826217

RESUMO

Operando-sensitive spectroscopic techniques were employed for investigating the changes in the molecular structure of the Cr sites in the CrVI/SiO2 Phillips catalyst during ethylene polymerization. Practically, the most arduous barrier to be overcome was the separation of the chromates reduction carried out by ethylene from the subsequent polymerization. By carefully tuning the experimental parameters we succeeded in observing these two events separately. We found that the sites involved in ethylene polymerization are mainly divalent Cr ions in a 6-fold coordination, in interaction with the oxygenated byproduct (mostly methylformate, generated from the disproportionation of two formaldehyde molecules). Unreduced CrVI species are also present during ethylene polymerization as well as reduced Cr species (either CrII or CrIII) acting as spectators. Our results challenge the old vision of "naked" chromium species (i.e., low coordinated) as the active sites and attribute a fundamental role to external (and flexible) oxygenated ligands that resemble the ancillary ligands in homogeneous polymerization catalysis.

18.
Breast Cancer Res ; 19(1): 106, 2017 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-28893303

RESUMO

BACKGROUND: Neoadjuvant-chemotherapy (NAC) is considered the standard treatment for locally advanced breast carcinomas. Accurate assessment of disease response is fundamental to increase the chances of successful breast-conserving surgery and to avoid local recurrence. The purpose of this study was to compare contrast-enhanced spectral mammography (CESM) and contrast-enhanced-MRI (MRI) in the evaluation of tumor response to NAC. METHODS: This prospective study was approved by the institutional review board and written informed consent was obtained. Fifty-four consenting women with breast cancer and indication of NAC were consecutively enrolled between October 2012 and December 2014. Patients underwent both CESM and MRI before, during and after NAC. MRI was performed first, followed by CESM within 3 days. Response to therapy was evaluated for each patient, comparing the size of the residual lesion measured on CESM and MRI performed after NAC to the pathological response on surgical specimens (gold standard), independently of and blinded to the results of the other test. The agreement between measurements was evaluated using Lin's coefficient. The agreement between measurements using CESM and MRI was tested at each step of the study, before, during and after NAC. And last of all, the variation in the largest dimension of the tumor on CESM and MRI was assessed according to the parameters set in RECIST 1.1 criteria, focusing on pathological complete response (pCR). RESULTS: A total of 46 patients (85%) completed the study. CESM predicted pCR better than MRI (Lin's coefficient 0.81 and 0.59, respectively). Both methods tend to underestimate the real extent of residual tumor (mean 4.1mm in CESM, 7.5mm in MRI). The agreement between measurements using CESM and MRI was 0.96, 0.94 and 0.76 before, during and after NAC respectively. The distinction between responders and non-responders with CESM and MRI was identical for 45/46 patients. In the assessment of CR, sensitivity and specificity were 100% and 84%, respectively, for CESM, and 87% and 60% for MRI. CONCLUSION: CESM and MRI lesion size measurements were highly correlated. CESM seems at least as reliable as MRI in assessing the response to NAC, and may be an alternative if MRI is contraindicated or its availability is limited.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Mama/diagnóstico por imagem , Terapia Neoadjuvante , Adulto , Idoso , Mama/efeitos dos fármacos , Mama/patologia , Neoplasias da Mama/patologia , Meios de Contraste/uso terapêutico , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Mamografia/métodos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/patologia , Estudos Prospectivos , Resultado do Tratamento
19.
BMC Plant Biol ; 17(1): 237, 2017 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-29221437

RESUMO

BACKGROUND: Microtubules, polymerized from alpha and beta-tubulin monomers, play a fundamental role in plant morphogenesis, determining the cell division plane, the direction of cell expansion and the deposition of cell wall material. During polarized pollen tube elongation, microtubules serve as tracks for vesicular transport and deposition of proteins/lipids at the tip membrane. Such functions are controlled by cortical microtubule arrays. Aim of this study was to first characterize the flax ß-tubulin family by sequence and phylogenetic analysis and to investigate differential expression of ß-tubulin genes possibly related to fibre elongation and to flower development. RESULTS: We report the cloning and characterization of the complete flax ß-tubulin gene family: exon-intron organization, duplicated gene comparison, phylogenetic analysis and expression pattern during stem and hypocotyl elongation and during flower development. Sequence analysis of the fourteen expressed ß-tubulin genes revealed that the recent whole genome duplication of the flax genome was followed by massive retention of duplicated tubulin genes. Expression analysis showed that ß-tubulin mRNA profiles gradually changed along with phloem fibre development in both the stem and hypocotyl. In flowers, changes in relative tubulin transcript levels took place at anthesis in anthers, but not in carpels. CONCLUSIONS: Phylogenetic analysis supports the origin of extant plant ß-tubulin genes from four ancestral genes pre-dating angiosperm separation. Expression analysis suggests that particular tubulin subpopulations are more suitable to sustain different microtubule functions such as cell elongation, cell wall thickening or pollen tube growth. Tubulin genes possibly related to different microtubule functions were identified as candidate for more detailed studies.


Assuntos
Linho/genética , Família Multigênica , Proteínas de Plantas/genética , Tubulina (Proteína)/genética , Sequência de Aminoácidos , Parede Celular/metabolismo , Evolução Molecular , Linho/crescimento & desenvolvimento , Linho/metabolismo , Flores/crescimento & desenvolvimento , Flores/metabolismo , Hipocótilo/crescimento & desenvolvimento , Hipocótilo/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Caules de Planta/crescimento & desenvolvimento , Caules de Planta/metabolismo , Alinhamento de Sequência , Tubulina (Proteína)/química , Tubulina (Proteína)/metabolismo
20.
Anal Bioanal Chem ; 408(29): 8299-8316, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27695983

RESUMO

The analysis of feed composition in terms of ingredients is addressed by Regulation (EC) 767/2009 and is important for detecting economic fraud and for monitoring feed safety. Within the framework of the EU project Feed-code, we developed and internally validated a modular assay, relying on intron polymorphism, for the complete qualitative analysis of the botanical composition of feed and the quantitative determination of six target plant species. Main performance parameters of each module, such as applicability, repeatability, specificity, and limit of detection, were evaluated. The whole assay was applied to a set of feed-like samples and results were in agreement with the expected composition. Application to a large set of compound feed and individual raw materials revealed the occurrence of botanical impurities. When compared with microscopic analysis, the proposed method gave more reliable results. We conclude that the Feed-code prototype, readily upgradable to include more plant species, is worthy of consideration for a full validation through a collaborative trial. Graphical Abstract The modular Feed-code method for the authentication of feed botanical composition.


Assuntos
Ração Animal/análise , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Plantas Comestíveis/química , Sementes/química , Ração Animal/normas , DNA de Plantas/genética , Eletroforese Capilar , Análise de Alimentos/legislação & jurisprudência , Contaminação de Alimentos/legislação & jurisprudência , Rotulagem de Alimentos , Regulamentação Governamental , Plantas Comestíveis/genética , Reação em Cadeia da Polimerase em Tempo Real , Sementes/genética , Transcriptoma
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