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1.
Appl Radiat Isot ; 212: 111465, 2024 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-39102778

RESUMO

Radiocarbon dating of samples from benzene synthesis by low-level Liquid Scintillation Counting (LSC) method requires the availability of 14C standards in benzene, which are difficult to obtain, or the use of an absolute measurement which is out of reach for most analytical laboratories. This paper describes how the CIEMAT/NIST method can help to solve this issue and presents the measurements of low activity concentrations performed in the LRI-D using two different benzene base scintillator cocktails.

2.
Radiologia (Engl Ed) ; 66(3): 228-235, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38908884

RESUMO

OBJECTIVES: To review the tolerance to and medium-term efficacy of ultrasound-guided cryoablation as an alternative to surgical treatment of fibroadenomas of the breast in our hospital. METHODS: We analyzed data from the 12 patients with fibroadenomas treated with ultrasound-guided cryoablation in our hospital between November 2020 and July 2022. Cryoablation was performed with a system using argon gas (Galil Boston Scientific®) or liquid nitrogen (Prosense Ice Cure®) following a triple-phase (freeze-thaw-freeze) protocol of variable duration depending on the size of the lesion. Patients were followed up with ultrasonography at 3, 6, 12, and 18 months. RESULTS: All patients tolerated the procedure well. Two patients reported moderate pain in the hours immediately after the procedure; no other complications occurred. The findings during follow-up included decreased volume of the fibroadenoma (47.07% at 3 months, 77.79% at 6 months, 81.77% at 12 months, and 88.81% at 18 months), blurring of the nodule's margins, a significantly reduced or absent signal within the lesion in the Doppler study, an echogenic band (representing edema, hemorrhage, and fat necrosis), and hypoechoic areas suggestive of fibrosis surrounding the fibroadenoma. CONCLUSIONS: Cryoablation is done on an outpatient basis, avoiding general anesthesia, thus making it less expensive. Cryoablation yields better cosmetic results than surgery.


Assuntos
Neoplasias da Mama , Criocirurgia , Fibroadenoma , Ultrassonografia de Intervenção , Humanos , Criocirurgia/métodos , Neoplasias da Mama/cirurgia , Neoplasias da Mama/diagnóstico por imagem , Fibroadenoma/cirurgia , Fibroadenoma/diagnóstico por imagem , Feminino , Adulto , Ultrassonografia de Intervenção/métodos , Pessoa de Meia-Idade , Resultado do Tratamento , Estudos Retrospectivos
3.
J Hosp Infect ; 149: 56-64, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38735628

RESUMO

BACKGROUND: Pseudomonas aeruginosa bloodstream infections (PA-BSIs) are a serious disease and a therapeutic challenge due to increasing resistance to carbapenems. Our objectives were to describe the prevalence and risk factors associated with carbapenem resistance (CR) and mortality in children with PA-BSI. METHODS: A retrospective, multi-centre study was carried out, including patients aged <20 years with PA-BSI in four tertiary hospitals in Madrid (Spain) during 2010-2020. Risk factors for CR PA-BSIs and 30-day mortality were evaluated in a multi-variable logistic regression model. RESULTS: In total, 151 patients with PA-BSI were included, with a median age of 29 months (interquartile range: 3.5-87.1). Forty-five (29.8%) cases were CR, 9.9% multi-drug resistant and 6.6% extensively drug resistant. The prevalence of CR remained stable throughout the study period, with 26.7% (12/45) of CR mediated by VIM-type carbapenemase. Patients with BSIs produced by CR-PA were more likely to receive inappropriate empiric treatment (53.3% vs 5.7%, P<0.001) and to have been previously colonized by CR-PA (8.9% vs 0%, P=0.002) than BSIs caused by carbapenem-susceptible P. aeruginosa. CR was associated with carbapenem treatment in the previous month (adjusted odds ratio (aOR) 11.15) and solid organ transplantation (aOR 7.64). The 30-day mortality was 23.2%, which was associated with mechanical ventilation (aOR 4.24), sepsis (aOR 5.72), inappropriate empiric antibiotic therapy (aOR 5.86), and source control as a protective factor (aOR 0.16). CONCLUSION: This study shows a concerning prevalence of CR in children with PA-BSIs, leading to high mortality. Inappropriate empiric treatment and sepsis were associated with mortality. The high prevalence of CR with an increased risk of inappropriate empiric treatment should be closely monitored.


Assuntos
Bacteriemia , Carbapenêmicos , Infecções por Pseudomonas , Pseudomonas aeruginosa , Humanos , Infecções por Pseudomonas/mortalidade , Infecções por Pseudomonas/epidemiologia , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/microbiologia , Pré-Escolar , Criança , Fatores de Risco , Masculino , Feminino , Pseudomonas aeruginosa/efeitos dos fármacos , Estudos Retrospectivos , Lactente , Carbapenêmicos/farmacologia , Carbapenêmicos/uso terapêutico , Adolescente , Bacteriemia/mortalidade , Bacteriemia/microbiologia , Bacteriemia/epidemiologia , Bacteriemia/tratamento farmacológico , Espanha/epidemiologia , Prevalência , Centros de Atenção Terciária/estatística & dados numéricos , Antibacterianos/uso terapêutico , Antibacterianos/farmacologia , Análise de Sobrevida , Resistência beta-Lactâmica
4.
Phys Rev Lett ; 131(9): 091801, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37721818

RESUMO

We measured the nuclear-recoil ionization yield in silicon with a cryogenic phonon-sensitive gram-scale detector. Neutrons from a monoenergetic beam scatter off of the silicon nuclei at angles corresponding to energy depositions from 4 keV down to 100 eV, the lowest energy probed so far. The results show no sign of an ionization production threshold above 100 eV. These results call for further investigation of the ionization yield theory and a comprehensive determination of the detector response function at energies below the keV scale.

5.
J Hosp Infect ; 139: 33-43, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37331378

RESUMO

BACKGROUND: Antimicrobial resistance (AMR) has become a significant challenge in high-complexity healthcare settings. AIM: To evaluate the prevalence of AMR in bloodstream isolates from high-complexity paediatric units in Spain over a nine-year period. METHODS: A retrospective observational multicentre study was conducted in three tertiary hospitals, analysing bloodstream isolates from patients aged <18 years admitted to the paediatric intensive care, neonatology, and oncology-haematology units between 2013 and 2021. Demographics, antimicrobial susceptibility, and resistance mechanisms were analysed in two periods (2013-2017 and 2017-2021). FINDINGS: In all, 1255 isolates were included. AMR was more prevalent in older patients and those admitted to the oncology-haematology unit. Multidrug resistance was observed in 9.9% of Gram-negative bacteria (GNB); 20.0% of P. aeruginosa vs 8.6% of Entero-bacterales (P < 0.001), with an increase in Enterobacterales from 6.2% to 11.0% between the first and the second period (P = 0.021). Difficult-to-treat resistance was observed in 2.7% of GNB; 7.4% of P. aeruginosa vs 1.6% of Enterobacterales (P < 0.001), with an increasing trend in Enterobacterales from 0.8% to 2.5% (P = 0.076). Carbapenem resistance among Enterobacterales increased from 3.5% to 7.2% (P = 0.029), with 3.3% producing carbapenemases (67.9% VIM). Meticillin resistance was observed in 11.0% of S. aureus and vancomycin resistance in 1.4% of Enterococcus spp., with both rates remaining stable throughout the study period. CONCLUSION: This study reveals a high prevalence of AMR in high-complexity paediatric units. Enterobacterales showed a concerning increasing trend in resistant strains, with higher rates among older patients and those admitted to oncology-haematology units.


Assuntos
Antibacterianos , Farmacorresistência Bacteriana , Criança , Humanos , Idoso , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Estudos Retrospectivos , Espanha/epidemiologia , Staphylococcus aureus , Testes de Sensibilidade Microbiana , Bactérias Gram-Negativas , Pseudomonas aeruginosa
6.
Arch Soc Esp Oftalmol (Engl Ed) ; 98(5): 270-275, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37031736

RESUMO

AIMS: To describe the changes in vessel density (VD) using optical coherence tomography angiography (OCTA) of the different sectors in the macular area between retinitis pigmentosa (RP) patients and controls. METHODS: Observational case-control study. We initially included 22 patients with RP and 21 controls. We obtained 6 × 6 OCTA images of the macular area using Angio-OCT SS-DRI-Triton 1.22 (Topcon, Japan), together with visual acuity, biomicroscopy, visual field and optical coherence tomography examination. We compared the VD values in both groups for both superficial (SVP) and deep vascular plexus (DVP). Correlation between VD and macular thickness was also calculated. RESULTS: The mean visual field index (VFI) in the RP group was 26.11% (±17.29). VD was significantly lower in the RP group compared with healthy controls in all sectors of the DVP (Superior 43.48 ±â€¯3.79 vs 48.86 ±â€¯2.62, P < .0001; Nasal 40,52 ±â€¯4.30 vs 46,01 ±â€¯3.23, P = .0002; Inferior 42.76 ±â€¯5.26 vs 50.10 ±â€¯3.36, P < .0001; Temporal 40.42 ±â€¯4.46 vs 46.09 ±â€¯2.91, P = .0001) and in all but nasal sector in the SVP (Superior 39.86 ±â€¯4.46 vs 46.47 ±â€¯2.61, P < .0001; Nasal 40.35 ±â€¯4.56 vs 44.09 ±â€¯2.87, P = .0067; Inferior 40.74 ±â€¯4.61 vs 46.58 ±â€¯3.26, P = .0002; Temporal 39.98 ±â€¯5.07 vs 44.78 ±â€¯3.28, P = .0024). Correlation between VD and macular thickness was positive and significant (RP: r = 0.59, P = .043; controls r = 0.51, P = .018). CONCLUSIONS: Patients with advanced forms of RP have less vessel density in the macular area than healthy subjects. These differences are present in all four quadrants in the DVP and three in the SVP.


Assuntos
Vasos Retinianos , Retinose Pigmentar , Humanos , Angiofluoresceinografia/métodos , Vasos Retinianos/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Estudos de Casos e Controles , Benchmarking , Retinose Pigmentar/diagnóstico por imagem
7.
Radiologia (Engl Ed) ; 65(2): 112-121, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37059577

RESUMO

OBJECTIVES: The primary objective of this study to determine whether infiltrating carcinoma is present in surgical specimens obtained after ultrasound-guided cryoablation from patients with HER2-negative luminal breast cancer without positive axillary lymph nodes at ultrasound. The secondary objective is to demonstrate that placing the presurgical seed-marker immediately before cryoablation does not interfere with the disappearance of tumor cells from freezing or in the surgeon's ability to locate the tumor. METHODS: We treated 20 patients diagnosed with unifocal HR-positive HER2-negative infiltrating ductal carcinoma measuring <2cm by means of ultrasound-guided cryoablation (ICEfx Galil, Boston Scientific) using a triple-phase (freezing‒passive thawing‒freezing; 10min each phase) protocol. All patients later underwent tumorectomy according to the routine operating-room agenda. RESULTS: No infiltrating carcinoma cells were detected in the post-cryoablation surgical specimen in 19 patients; a focus of infiltrating carcinoma cells measuring <1mm was detected in the remaining patient. CONCLUSION: In the near future, if confirmed in larger studies with longer follow-up, cryoablation might constitute a safe and efficacious technique for the treatment of early, low-risk infiltrating ductal carcinoma. In our series, marking with ferromagnetic seeds did not interfere with the efficacy of the procedure or of the subsequent surgical intervention.


Assuntos
Neoplasias da Mama , Carcinoma Ductal , Carcinoma , Criocirurgia , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Neoplasias da Mama/patologia , Criocirurgia/métodos , Carcinoma/cirurgia , Ultrassonografia de Intervenção
8.
J Endocrinol Invest ; 46(11): 2275-2286, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37002436

RESUMO

INTRODUCTION: Pituitary neuroendocrine tumors (PitNETs) represent 15-18.2% of all intracranial tumors. Their clinical presentation can range from chronic headache, visual defects, hypopituitarism to hormone excess syndromes. PitNETS are commonly classified as functioning neuroendocrine tumors (F-PitNETs) and non-functioning neuroendocrine tumors (NF-PitNETs). At the moment, new classification has emerged based on cell lineages. Almost 50% of all patients with PitNETs require surgical intervention, and about 25% of these have residual and persistent disease that may require additional management. SUBJECTS AND METHODS: A retrospective cohort of medical records of patients with PitNETs, aiming to describe the incidence of recurrence of patients who received surgical treatment over a 12 month follow up period at San Jose Hospital (SJH) in Bogotá, Colombia, over an observation period of 10 years. Furthermore, clinical presentation, biochemical characteristics and immunohistochemistry, postoperative complications are detailed. RESULTS: Eight hundred and eighty-seven patients with pituitary tumors were included in the cohort; 83% (737/887) had a diagnosis of PitNET. Of these, 18.9% (140) received surgical management. The majority 58% (98/140) had nonfunctional-PitNETs (NF-PitNETs), followed by growth-hormone-secreting pituitary adenoma (22.1%; 33/140), adrenocorticotropic- hormone-secreting pituitary adenoma (9.3%; 13/140), and prolactinomas (9.3%; 13/140). A recurrence was found in 45.71% (64/140), subclassified as biochemical in 15.71% (22/140), controlled with medications in 20% (28/140), and remission occurred in 18.57% (26/140). CONCLUSION: Clinical presentation and incidence of recurrence in patients with PitNETs in a referral center in Colombia are similar to other surgical cohorts with low cure rates and high recurrence.


Assuntos
Adenoma Hipofisário Secretor de ACT , Adenoma , Tumores Neuroendócrinos , Neoplasias Hipofisárias , Humanos , Neoplasias Hipofisárias/diagnóstico , Neoplasias Hipofisárias/epidemiologia , Neoplasias Hipofisárias/terapia , Colômbia/epidemiologia , Estudos Retrospectivos , Tumores Neuroendócrinos/diagnóstico , Tumores Neuroendócrinos/epidemiologia , Tumores Neuroendócrinos/cirurgia , Adenoma Hipofisário Secretor de ACT/cirurgia , Adenoma/diagnóstico , Adenoma/epidemiologia , Adenoma/terapia , Hormônios
9.
Microb Pathog ; 176: 106017, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36736545

RESUMO

The primary replication site of Influenza A virus (IAV) is type II alveolar epithelial cells (AECII), which are central to normal lung function and present important immune functions. Surfactant components are synthesized primarily by AECII, which play a crucial role in host defense against infection. The aim of this study was to analyze if the impact of influenza infection is differential between A(H1N1)pdm09 and A/Victoria/3/75 (H3N2) on costimulatory molecules and ProSP-C expression in AECII from BALB/c mice infected and A549 cell line infected with both strains. Pandemic A(H1N1)pdm09 and A/Victoria/3/75 (H3N2) were used to infect BALB/c mice and the A549 cell line. We evaluated the surface expression of co-stimulatory molecules (CD45/CD31/CD74/ProSP-C) in AECII and A549 cell lines. Our results showed a significant decrease in ProSP-C+ CD31- CD45- and CD74+ CD31- CD45- expression in AECII and A549 cell line with the virus strain A(H1N1)pdm09 versus A/Victoria/3/75 (H3N2) and controls (non-infection conditions). Our findings indicate that changes in the expression of ProSP-C in AECII and A549 cell lines in infection conditions could result in dysfunction leading to decreased lung compliance, increased work of breathing and increased susceptibility to injury.


Assuntos
Alphainfluenzavirus , Vírus da Influenza A Subtipo H1N1 , Influenza Humana , Animais , Humanos , Camundongos , Células Epiteliais Alveolares , Vírus da Influenza A Subtipo H3N2 , Tensoativos
10.
Appl Radiat Isot ; 193: 110667, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36682308

RESUMO

A comprehensive radioactivity characterisation of Castilla y León (Spain) groundwater intakes intended for human consumption is addressed between 2017 and 2021. This study responds to the radiological requirements stated in the European Council Directive 51/2013/EURATOM concerning drinking water for public health. Given that the gross α- and gross ß-activity determination is used as a screening strategy for water radioactivity monitoring, the reliability of the thin-source deposit method (ISO 10704, 2019) has been improved to achieve representative values of the total activity coming from α- and ß-particle emitters in the samples. More than 400 groundwater samples have been considered for this purpose, analysing their 238,235,234U, 228,226Ra, 210Pb, and 210Po activity concentrations, which are needed for the indicative dose assessment. These results, considered reference activity values, are compared with the gross α- and gross ß-activities determined by the different procedure approaches. Ultimately, the results of the liquid scintillation counting method (ISO 11704, 2018) are also used to validate the optimised method.


Assuntos
Água Potável , Monitoramento de Radiação , Radioatividade , Poluentes Radioativos da Água , Humanos , Água Potável/análise , Reprodutibilidade dos Testes , Monitoramento de Radiação/métodos , Poluentes Radioativos da Água/análise
11.
Neurologia (Engl Ed) ; 38(6): 412-418, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35842129

RESUMO

INTRODUCTION: Ischaemic stroke (IS) due to cervical and cerebral artery dissection (CAD) is a rare entity, and few data are available on the use of such reperfusion therapies as intravenous fibrinolysis and mechanical thrombectomy in these patients. We analysed the use of these treatments in patients with IS due to CAD and compared them against patients receiving reperfusion treatment for IS of other aetiologies. METHODS: We conducted an observational, retrospective, multicentre study of patients with IS due to CAD recorded in the National Stroke Registry of the Spanish Society of Neurology during the period 2011-2019. Comparative analyses were performed between: a) patients with CAD treated and not treated with reperfusion therapies and b) patients treated with reperfusion for IS due to CAD and patients treated with reperfusion for IS due to other causes. Epidemiological data, stroke variables, and outcomes at discharge and at 3 months were included in the analysis. RESULTS: The study included 21,037 patients with IS: 223 (1%) had IS due to CAD, of whom 68 (30%) received reperfusion treatment. Reperfusion treatments were used less frequently in cases of vertebral artery dissection and more frequently in patients with carotid artery occlusion. Compared to patients with IS due to other causes, patients with CAD were younger, more frequently underwent mechanical thrombectomy, and less frequently received intravenous fibrinolysis. Rates of haemorrhagic complications, mortality, and independence at 3 months were similar in both groups. CONCLUSIONS: Reperfusion therapy is frequently used in patients with IS due to CAD. The outcomes of these patients demonstrate the efficacy and safety of reperfusion treatments, and are comparable to the outcomes of patients with IS due to other aetiologies.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/etiologia , Isquemia Encefálica/terapia , Isquemia Encefálica/complicações , Estudos Retrospectivos , Resultado do Tratamento , AVC Isquêmico/complicações , Reperfusão/métodos , Artérias Cerebrais
12.
Med Oral Patol Oral Cir Bucal ; 28(1): e65-e71, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36173718

RESUMO

BACKGROUND: Descending necrotising mediastinitis is one of the most lethal and least frequent forms of mediastinitis. It is a life-threatening infection most frequently originating from an oropharyngeal or odontogenic infection. MATERIAL AND METHODS: A retrospective study of 6 patients diagnosed and treated for descending necrotising mediastinitis between 2015 and 2020 is reported. RESULTS: All patients were male, mean age of 34.83 years; 66% were smokers. 83% had an orocervical infection and 34% had initial mediastinal spread. All patients were treated initially with empirical broad-spectrum antibiotics and surgical drainage, with subsequent admission to the Intensive Care Unit; only one of them required tracheostomy. The mean hospital stay was 27.37 days. After a mean follow-up of 6 months, 100% of the cases had a complete recovery. CONCLUSIONS: Early diagnosis and surgical treatment combined with improved life-support treatment in intensive care units and broad-spectrum antibiotic therapy leads to a decrease in associated mortality.


Assuntos
Mediastinite , Humanos , Masculino , Adulto , Feminino , Mediastinite/diagnóstico , Mediastinite/cirurgia , Taxa de Sobrevida , Estudos Retrospectivos , Necrose , Antibacterianos/uso terapêutico
14.
Rev Esp Cir Ortop Traumatol ; 66(1): 68-73, 2022.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33663991

RESUMO

INTRODUCTION: One of the most frequently treated pathologies in our department are tendon lesions that affect the rotator cuff of the shoulder. There are different types of treatment for massive or irreparable tears. For a few years, a low-invasive technique was introduced based on the placement of a biodegradable subacromial spacer. The objective of the work is to analyse the results of our experience with the use of this device (InSpaceTM). MATERIAL AND METHOD: The study collects the results obtained in 25 patients with irreparable ruptures of rotator cuff defined by RM, in which they were implanted a balloon subacromial in our centre in the period from January 2015 - until December 2017. All patients were evaluated preoperatively and one year after surgery including the visual analogue scale (VAS), the Constant test (CS) and the QuickDASH (QD). RESULTS: Of the 25 patients, 5 patients (20%) were operated by arthroscopy and 20 (80%) By open approach (mini-open). A total of 22 patients completed the follow-up year. At 12 months, 64% of the patients obtained an improvement of at least 10 points in the CS. Patients departed from an initial average CS of 32 points that improved to 54.9 points of average in the postoperative evaluation at 12 months (average improvement 22.9 points; Value-p < 0.05). In terms of pain assessment, in our study, 87% of patients obtained an improvement of at least 2 points in the EVA at 12 months of follow-up (P-value < 0.05). Patients departed from an initial average EVA of 8.7 that improved to 3.7 points average at 12 months. 73% of the patients responded to be satisfied with the intervention and would return to the surgery. CONCLUSIóN: The results obtained in our series to one year of follow-up speak in favour of the use of the Subacromial Balloon (InSpaceTM), as a therapeutic option available for patients with irreparable ruptures of the rotator cuff. It can be used as an interim procedure, delaying the need for more invasive surgery, or as a definitive procedure in patients medically non-candidates for reverse arthroplasty. It is important to have clear indications of this procedure in order not to make mistakes.

15.
Evolution ; 75(12): 3142-3153, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34643274

RESUMO

The past decades have provided valuable information on how animals age in the wild. However, examples of male reproductive senescence are scarce. In particular, few studies have described an age-related decline in the expression of conspicuous traits influencing mating success. Red ornaments could be good candidates to detect this decline because their expression may depend on the availability of pigments (carotenoids) related to oxidative stress, the latter frequently linked to senescence. Furthermore, it has been argued that efficient mitochondrial metabolism is key to express red carotenoid-based ornaments, and mitochondrial dysfunction is usually associated with senescence. We studied the age-linked expression of a red carotenoid-based trait: the yellow-to-red plumage coloration of male common crossbills (Loxia curvirostra). This coloration has recently been experimentally related to mitochondrial function. Here, we analyzed longitudinal plumage coloration data obtained throughout 28 years in free-living birds. We detected an initial increase in redness during the first 2 years of life and a subsequent decline. The relationship between color and age was unrelated to within-individual body mass variability. As far as we know, this is the first demonstration of an age-related ketocarotenoid-based color decrease detected by simultaneously testing within- and between-individual variability in wild animals.


Assuntos
Animais Selvagens , Passeriformes , Animais , Carotenoides/metabolismo , Masculino , Estresse Oxidativo , Pigmentação
16.
Nanoscale Adv ; 3(12): 3491-3496, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36133728

RESUMO

Scientific interest in iron-oxides and in particular magnetite has been renewed due to the broad scope of their fascinating properties, which are finding applications in electronics and biomedicine. Specifically, iron oxide nanoparticles (IONPs) are gathering attraction in biomedicine. Their cores are usually constituted by a mixture of maghemite and magnetite phases. In view of this, to fine-tune the properties of an ensemble of IONPs towards their applications, it is essential to enhance mass fabrication processes towards the production of monodisperse IONPs with controlled size, shape, and stoichiometry. We exploit the vacancy sensitivity of the Verwey transition to detect the presence of magnetite. Here we provide direct evidence for the Verwey transition in an ensemble of IONPs through neutron diffraction. This transition is observed as a variation in the Fe magnetic moment at octahedral sites and, in turn, gives rise to a change of the net magnetic moment. Finally, we show this variation as the microscopic ingredient driving the characteristic kink that hallmarks the Verwey transition in thermal variation of magnetization.

17.
Neurologia (Engl Ed) ; 2020 Dec 21.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33358059

RESUMO

INTRODUCTION: Ischaemic stroke (IS) due to cervical and cerebral artery dissection (CAD) is a rare entity, and few data are available on the use of such reperfusion therapies as intravenous fibrinolysis and mechanical thrombectomy in these patients. We analysed the use of these treatments in patients with IS due to CAD and compared them against patients receiving reperfusion treatment for IS of other aetiologies. METHOD: We conducted an observational, retrospective, multicentre study of patients with IS due to CAD recorded in the National Stroke Registry of the Spanish Society of Neurology during the period 2011-2019. Comparative analyses were performed between: a) patients with CAD treated and not treated with reperfusion therapies and b) patients treated with reperfusion for IS due to CAD and patients treated with reperfusion for IS due to other causes. Epidemiological data, stroke variables, and outcomes at discharge and at 3 months were included in the analysis. RESULTS: The study included 21,037 patients with IS: 223 (1%) had IS due to CAD, of whom 68 (30%) received reperfusion treatment. Reperfusion treatments were used less frequently in cases of vertebral artery dissection and more frequently in patients with carotid artery occlusion. Compared to patients with IS due to other causes, patients with CAD were younger, more frequently underwent mechanical thrombectomy, and less frequently received intravenous fibrinolysis. Rates of haemorrhagic complications, mortality, and independence at 3 months were similar in both groups. CONCLUSIONS: Reperfusion therapy is frequently used in patients with IS due to CAD. The outcomes of these patients demonstrate the efficacy and safety of reperfusion treatments, and are comparable to the outcomes of patients with IS due to other aetiologies.

18.
Rev Neurol ; 71(8): 292-297, 2020 Oct 16.
Artigo em Espanhol | MEDLINE | ID: mdl-33034367

RESUMO

INTRODUCTION: Idiopathic intracranial hypertension is an entity with an incidence of approximately 1.2: 100,000 inhabitants/year. It affects in a greater proportion obese women and women of childbearing age. Headache is the most characteristic symptom, followed by visual disturbances. In recent years, the diagnosis of dural sinus stenosis has increased in cases of intracranial hypertension resistant to conventional treatment. For this reason, the development of endovascular therapy as a therapeutic option in selected patients is booming. CASE REPORTS: We present three cases of intracranial hypertension secondary to dural sinus stenosis, diagnosed and treated in our hospital. Despite the establishment of adequate diuretic treatment and the performance of invasive procedures to bypass the cerebrospinal fluid, they persisted with neurological symptoms and visual deficits. After verifying that they fulfilled the requirements described in the literature, they underwent intracranial stenting, with satisfactory results in all of them, achieving the disappearance of the headache and recovery of visual acuity. CONCLUSION: Stenting of dural sinus stenosis as a cause of intracranial hypertension is an increasingly used technique, which has presented favorable results. Studies are necessary to know its long-term impact.


TITLE: Tratamiento endovascular de la estenosis de los senos venosos intracraneales en la hipertensión intracraneal: descripción de tres casos y discusión de la bibliografía.Introducción. La hipertensión intracraneal idiopática es una entidad con una incidencia anual aproximada de 1,2 por cada 100.000 habitantes. Afecta en mayor proporción a mujeres obesas y en edad fértil. La cefalea es el síntoma más característico, seguido de las alteraciones visuales. En los últimos años, se ha incrementado el diagnóstico de la estenosis de los senos durales en los casos de hipertensión intracraneal resistentes al tratamiento convencional. Por ello, se encuentra en auge el desarrollo de la terapia endovascular como opción terapéutica en pacientes seleccionados. Casos clínicos. Se presentan tres casos de hipertensión intracraneal secundaria a estenosis de los senos durales, diagnosticados y tratados en nuestro hospital. A pesar de la instauración del adecuado tratamiento diurético y de la realización de procedimientos invasivos de derivación del líquido cefalorraquídeo, persistían la clínica neurológica y el déficit visual. Tras comprobar que cumplían los requisitos descritos en la bibliografía, se sometieron a la implantación de stent intracraneal (stenting), con resultado satisfactorio en todos ellos, logrando la desaparición de la cefalea y la recuperación de la agudeza visual. Conclusión. El stenting de la estenosis de los senos durales como causa de hipertensión intracraneal es una técnica cada vez más utilizada que ha presentado resultados favorables. Es necesaria la realización de estudios para conocer su impacto a largo plazo.


Assuntos
Pseudotumor Cerebral , Stents , Constrição Patológica , Feminino , Humanos , Pseudotumor Cerebral/complicações , Pseudotumor Cerebral/terapia , Transtornos da Visão/etiologia
19.
Exp Oncol ; 42(2): 101-108, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32602283

RESUMO

BACKGROUND: Blueberries are among the fruits with the highest antioxidant activity and have been recognized by their health promoting properties. AIM: In vitro study of the anti-proliferative effects of a blueberry extract on a panel of cancer cells from different origin. MATERIALS AND METHODS: A blueberry extract was produced using ethanol as extracting solvent. The anti-proliferative activity of the extract was evaluated against seven tumor cell lines. The properties of blueberry extract to decrease cell adhesion and migration were also investigated. RESULTS: Blueberry extract showed a dose-dependent inhibitory effect on cell proliferation for all cell lines. Non-cytotoxic concentrations of the extract decreased cell adhesion in five of seven cell lines studied and inhibited the migration of MDA-MB-231 and PC-3 tumor cells. CONCLUSION: This work provides additional evidence regarding the ability of blueberry extract to inhibit the growth and decrease cell adhesion and migration of different cancer cell lines in vitro.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Mirtilos Azuis (Planta)/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Antocianinas/análise , Antineoplásicos Fitogênicos/química , Antioxidantes/química , Antioxidantes/farmacologia , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Masculino , Polifenóis/análise
20.
Chem Soc Rev ; 2020 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-32658221

RESUMO

Polymers are ubiquitously present in our daily life because they can meet a wide range of needs and fields of applications. This success, based on an irresponsible linear consumption of plastics and the access to cheap oil, is creating serious environmental problems. Two lines of actions are needed to cope with them: to adopt a circular consumption of plastics and to produce renewable carbon-neutral monomers. This review analyses the recent advances in the chemocatalytic processes for producing biomass-derived carboxylic acids. These renewable carboxylic acids are involved in the synthesis of relevant general purpose and specialty polyesters and polyamides; some of them are currently derived from oil, while others can become surrogates of petrochemical polymers due to their excellent performance properties. Polyesters and polyamides are very suitable to be depolymerised to other valuable chemicals or to their constituent monomers, what facilitates the circular reutilisation of these monomers. Different types of carboxylic acids have been included in this review: monocarboxylic acids (like glycolic, lactic, hydroxypropanoic, methyl vinyl glycolic, methyl-4-methoxy-2-hydroxybutanoic, 2,5-dihydroxypent-3-enoic, 2,5,6-trihydroxyhex-3-enoic acids, diphenolic, acrylic and δ-amino levulinic acids), dicarboxylic acids (2,5-furandicarboxylic, maleic, succinic, adipic and terephthalic acids) and sugar acids (like gluconic and glucaric acids). The review evaluates the technology status and the advantages and drawbacks of each route in terms of feedstock, reaction pathways, catalysts and economic and environmental evaluation. The prospects and the new research that should be undertaken to overcome the main problems threatening their economic viability or the weaknesses that prevent their commercial implementation have also been underlined.

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