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1.
Chemistry ; 30(3): e202302955, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-37943001

RESUMEN

A model for the morphology (size, shape, and crystallinity) of carbon dots (CDs) in the solid state consistent with the observed photoluminescence in solution is proposed herein. Overwhelming evidence has been collected that links the data coming from solid-state analysis (high-resolution transmission electron microscopy (HRTEM), atomic force microscopy (AFM), and matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS)) to that of solution (pulsed-field gradient (PFG)-NMR spectroscopy, time-resolved fluorescence anisotropy (TRFA), and steady-state/time-resolved fluorescence), allowing the establishment of an overall structural model for CDs. According to this model, the so-called carbon dots, observed under HRTEM imaging, are in fact supramolecular organized structures dynamically assembled from small to medium-sized molecular species when the solvent is removed to give the solid form. In this way, the imaged nanoparticles (TEM/AFM) are not covalently bound entities formed during the synthetic process, but instead supramolecular entities formed by noncovalent interactions. These particles, if at all present in solution, have the form of loose associations of relatively small molecules. This study was conducted on CDs obtained from the hydrothermal carbonization (HTC) of a biomass waste (olive wet pomace).

2.
Chemistry ; 30(3): e202304122, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38109086

RESUMEN

Invited for the cover of this issue are José Prata and co-workers at Instituto Superior de Engenharia de Lisboa and Instituto Superior Técnico. The image depicts a model for the supramolecular nature of carbon dots. Read the full text of the article at 10.1002/chem.202302955.

3.
Arch Orthop Trauma Surg ; 143(12): 7035-7041, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37561166

RESUMEN

Failure of osteosynthesis is a common complication of the nailing of trochanteric fractures which typically occurs through form of cut-out. Tip-Apex distance (TAD), Calcar Tip-Apex distance (CalTAD), and Chang criteria are validated variables to predict failure of cephalomedullary nailing. This is a retrospective study which analyzes treatment of trochanteric fractures from 2018 to 2020 (n = 296) evaluating postoperative radiographs and factors of mechanical failure. Our objective was to assess correlation among these variables and their influence on mechanical failure, either individually or creating a new score. Our results support the CalTAD and Chang's criteria as valid predictors of mechanical failure. Furthermore, they empathize the importance of fracture reduction and proper placement of cervical screw. To our knowledge, this is the first study performing multivariate analysis including these 3 variables.


Asunto(s)
Fijación Intramedular de Fracturas , Fracturas de Cadera , Humanos , Estudios Retrospectivos , Clavos Ortopédicos , Fijación Intramedular de Fracturas/métodos , Fracturas de Cadera/diagnóstico por imagen , Fracturas de Cadera/cirugía , Tornillos Óseos , Resultado del Tratamiento
4.
Environ Monit Assess ; 195(6): 697, 2023 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-37208521

RESUMEN

Water scarcity affects already a large part of the world's population. To overcome this situation, water management is needed, and wastewater reuse must be implemented and included as a new approach. To achieve that objective water quality must comply with the parameters established in the Regulation (EU) 2020/741 of the European Parliament and the Council of the European Union and new treatment solutions have to be developed. The main goal of this pilot study was to evaluate the peracetic acid (PAA) disinfection efficiency in a real wastewater treatment plant (WWTP) in order to accomplish the wastewater reuse objective. To this end, six disinfection conditions were studied, three PAA doses (5, 10, and 15) and three contact times (5, 10, and 15) based on the commonly used disinfection operational conditions in real WWTP. Comparing the Total Suspended Solids (TSS), turbidity, Biological Oxygen Demand (BOD5) and Escherichia coli content, after and before the disinfection step, was possible to conclude that PAA ensures the Regulation (EU) 2020/741 requirements and that the disinfected effluent can be reused for several uses. All the conditions in which the PAA dose was 15 mg/L and the condition with 10 mg/L of PAA with a contact time of 15 min were the most promising, presenting the second highest water quality class achieved. The results of this study illustrate the potential of PAA as an alternative disinfectant for wastewater treatment and, bring it closer to the water reuse objective by presenting several possibilities for water uses.


Asunto(s)
Desinfectantes , Purificación del Agua , Ácido Peracético , Aguas Residuales , Proyectos Piloto , Monitoreo del Ambiente , Desinfección/métodos , Escherichia coli , Purificación del Agua/métodos , Eliminación de Residuos Líquidos/métodos
5.
Molecules ; 27(19)2022 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-36235306

RESUMEN

Carbon nanomaterials endowed with significant luminescence have been synthesized for the first time from an abundant, highly localized waste, the wet pomace (WP), a semi-solid by-product of industrial olive oil production. Synthetic efforts were undertaken to outshine the photoluminescence (PL) of carbon nanoparticles through a systematic search of the best reaction conditions to convert the waste biomass, mainly consisting in holocellulose, lignin and proteins, into carbon dots (CDs) by hydrothermal carbonization processes. Blue-emitting CDs with high fluorescence quantum yields were obtained. Using a comprehensive set of spectroscopic tools (FTIR, Raman, XPS, and 1H/13C NMR) in combination with steady-state and time-resolved fluorescence spectroscopy, a rational depiction of WP-CDs structures and their PL properties was reached. WP-CDs show the up-conversion of PL capabilities and negligible cytotoxicity against two mammalian cell lines (L929 and HeLa). Both properties are excellent indicators for their prospective application in biological imaging, biosensing, and dynamic therapies driven by light.


Asunto(s)
Olea , Puntos Cuánticos , Animales , Carbono/química , Lignina , Luminiscencia , Mamíferos , Aceite de Oliva , Puntos Cuánticos/química
6.
Molecules ; 26(4)2021 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-33672924

RESUMEN

Presently, water quantity and quality problems persist both in developed and developing countries, and concerns have been raised about the presence of emerging pollutants (EPs) in water. The circular economy provides ways of achieving sustainable resource management that can be implemented in the water sector, such as the reuse of drinking water treatment sludges (WTSs). This study evaluated the potential of WTS containing a high concentration of activated carbon for the removal of two EPs: the steroid hormones 17ß-estradiol (E2) and 17α-ethinylestradiol (EE2). To this end, WTSs from two Portuguese water treatment plants (WTPs) were characterised and tested for their hormone adsorbance potential. Both WTSs showed a promising adsorption potential for the two hormones studied due to their textural and chemical properties. For WTS1, the final concentration for both hormones was lower than the limit of quantification (LOQ). As for WTS2, the results for E2 removal were similar to WTS1, although for EE2, the removal efficiency was lower (around 50%). The overall results indicate that this method may lead to new ways of using this erstwhile residue as a possible adsorbent material for the removal of several EPs present in wastewaters or other matrixes, and as such contributing to the achievement of Sustainable Development Goals (SDG) targets.


Asunto(s)
Aguas del Alcantarillado/química , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua , Elementos Químicos , Concentración de Iones de Hidrógeno , Minerales/análisis , Termogravimetría
7.
Transpl Int ; 33(10): 1262-1273, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32608073

RESUMEN

The donors' estimated glomerular filtration rate (eGFR) after living nephrectomy has been a concern, particularly in donors with smaller kindeys. Therefore, we developed this retrospective observational study in 195 donors to determine the ability remaining kidney volume indexed to weight (RKV/W) to predict eGFR at 1 year through multivariate linear regression and to explore this relationship between annual eGFR change from 1 to 4 years postdonation evaluated by a linear mixed model. Comparing RKV/W tertiles (T1, T2, T3), RKV/W was a good predictor of 1-year eGFR which was significantly better in T3 donors. Gender, predonation eGFR, and RKV/W were independent predictors of eGFR at 1-year. In a subgroup with predonation eGFR < 90mL/min/1.73 m2 , a significant prediction of eGFR < 60mL/min/1.73 m2 was detected in males with RKV/W ≤ 2.51cm3 /kg. Annual eGFR (ml/min/year) change from 1 to 4 years was + 0.77. RKV/W divided by tertiles (T1-T3) was the only significant predictor: T2 and T3 donors had an annual eGFR improvement opposing to T1. RKV/W was a good predictor of eGFR at 1 year, independently from predonation eGFR. A higher RKV/W was associated with improved eGFR at 1 year. A decline in eGFR on the four years after surgery was only noticeable in donors with RKV/W ≤ 2.13cm3 /kg.


Asunto(s)
Trasplante de Riñón , Donadores Vivos , Tasa de Filtración Glomerular , Humanos , Riñón/cirugía , Masculino , Nefrectomía , Estudios Retrospectivos
14.
Viruses ; 16(2)2024 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-38400001

RESUMEN

The resurgence of Mpox, predominantly among men who have sex with men (MSM), has prompted an analysis of its clinical manifestations and epidemiological patterns, particularly in individuals living with human immunodeficiency virus (HIV). This retrospective study aims to delineate and compare the clinical presentations and epidemiological characteristics of Mpox among HIV-positive and HIV-negative individuals. A total of 58 confirmed Mpox cases from a dermatology department in Lisbon were analyzed, focusing on mucocutaneous manifestations, systemic symptoms, and laboratory parameters. Our findings indicate no significant difference in disease severity and presentation between HIV-positive and HIV-negative groups, suggesting that HIV status may not be a determinant of Mpox severity, but rather an indicator of increased sexual risk behaviors, a recognized risk factor for Mpox transmission.


Asunto(s)
Infecciones por VIH , Seropositividad para VIH , Mpox , Minorías Sexuales y de Género , Masculino , Humanos , VIH , Estudios Retrospectivos , Homosexualidad Masculina , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología
15.
J Dermatolog Treat ; 35(1): 2345728, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38684228

RESUMEN

OBJECTIVES: Generalized pustular psoriasis (GPP) is a rare, life-threatening skin inflammatory disorder. This study aimed to describe the disease course, treatment strategies, and healthcare utilization among patients with GPP in Portugal. METHODS: This multicentric, observational, retrospective study included consecutive adult patients with GPP undergoing a dermatology evaluation in different reporting institutions by experienced dermatologists between 2002 and 2023. RESULTS: A total of 59 patients were assessed. Most of the cohort had a previous history of plaque psoriasis (71%) and 83% presented at least one comorbidity. At the initial encounter, 64% of the cohort needed hospitalization. Systemic involvement was common, including fever (37%), and elevated white blood cell count and erythrocyte sedimentation rate/C-reactive protein (49%). Nearly, 73% of patients initiated systemic drugs, and 70% had to discontinue the first treatment. During the study, 98% of patients experienced at least one flare. At the last visit, 3.4% of patients had died, and 71.2% exhibited signs of active disease despite undergoing treatment. CONCLUSIONS: Our study demonstrates that GPP is a chronic, debilitating condition associated with systemic involvement, frequent flares, and hospitalizations, despite receiving multiple systemic treatments. Improved disease awareness and new treatments are needed to improve patient care and decrease the burden of the disease.


Asunto(s)
Costo de Enfermedad , Hospitalización , Psoriasis , Humanos , Psoriasis/terapia , Psoriasis/patología , Psoriasis/tratamiento farmacológico , Psoriasis/diagnóstico , Estudios Retrospectivos , Portugal/epidemiología , Masculino , Femenino , Persona de Mediana Edad , Adulto , Hospitalización/estadística & datos numéricos , Anciano , Comorbilidad , Fármacos Dermatológicos/uso terapéutico , Aceptación de la Atención de Salud/estadística & datos numéricos , Índice de Severidad de la Enfermedad
16.
Cureus ; 15(8): e43852, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37736445

RESUMEN

Unilateral shoulder dislocation is known to be one of the most common joint dislocations. However, simultaneous bilateral shoulder dislocations are rare, especially anterior dislocations. We report a case of an 84-year-old woman who presented to the urgency room with symmetrical bilateral anterior shoulder dislocation 12 hours after falling on a treadmill. She presented with bilateral pain, functional impairment, prominent acromion, flattened shoulder, and, in the right upper limb, paresthesias on the dorsum of the hand and extension deficit of the fingers. Closed reduction of both shoulders was performed under sedation, and she was immobilized bilaterally with an arm sling in internal rotation. A full recovery was achieved six months after the injury.

17.
Cureus ; 15(9): e45661, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37868403

RESUMEN

Giant cell tumors (GCTs) of the ischium are rare and often diagnosed at an advanced stage. In fact, there is no defined treatment algorithm to treat this lesion. We present two case reports of Campanacci's stage three ischiopubic GCT confirmed with biopsy. They were effectively treated with excision of the ischiopubic ramus, aggressive curettage, drilling, and phenolization at the margins. The surgery was performed in a gynecological position with an approach over the ischiopubic ramus. Both cases present no recurrence (two and 10-year follow-up), and neither has a significant impact on the quality of life. A thorough plan and surgical technique were essential for the success of this intervention.

18.
Trauma Case Rep ; 48: 100960, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37928716

RESUMEN

Perilunate fracture dislocation with an elbow dislocation, it is referred to as a floating forearm. Very few cases have been described worldwide. We report a case of a 37-year-old man diagnosed with a floating forearm (trans-scaphoid perilunate fracture dislocation combined with a terrible triad injury), after a fall of the top of an olive tree. Urgent closed reduction of the elbow and wrist was obtained. A double approach to the wrist was used: dorsal approach to fix the scaphoid and to reduce the carpus and a volar approach to release the median nerve and repair the volar capsule. A lateral approach to the elbow was performed to fix the radial head and to repair the lateral collateral ligament. At 3 months postoperative, the patient had no pain in the elbow and in the wrist. He returned to Work with some restriction at 4-month post operatively.

19.
Cureus ; 15(9): e45849, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37881390

RESUMEN

A phytobezoar is a conglomerate of improperly digested fruit and vegetable debris, and its development is associated, amongst other factors, with previous gastric surgery. Most phytobezoars remain asymptomatic and are incidentally found during imaging or interventional procedures. However, in some patients, they can cause small bowel obstruction, which can subsequently lead to severe complications. Although the clinical findings are similar to other causes of intestinal obstruction, there are some particular diagnostic and treatment features more specific to phytobezoars. We present a case of an 85-year-old man with a history of previous antrectomy and Billroth II reconstruction who came to the emergency department with bilateral aspiration pneumonia and intestinal obstruction due to a bezoar. The CT scan showed bilateral inferior lobe pulmonary consolidation, as well as a marked dilation of the small bowel with gas-fluid levels and a transition to normal caliber in the terminal ileum, where an oval mottled-appearing mass suggesting a bezoar was present. An urgent laparotomy confirmed the diagnosis, and an enterotomy with removal of the bezoar was performed. Phytobezoars must be considered as a cause of intestinal obstruction, particularly when patients have a history of previous gastric surgery. Its radiological findings, particularly in CT scans, are specific and should be appreciated to establish the diagnosis promptly. The treatment of small bowel obstruction due to a phytobezoar requires surgery most of the time, and the surgeon must bear in mind the need to look for the existence of other bezoars in the gastrointestinal tract to prevent reoccurrence.

20.
J Agric Food Chem ; 70(2): 656-668, 2022 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-34982560

RESUMEN

The kinetics and thermodynamics of the pH-dependent reversible and irreversible processes leading to color fading of pelargonidin-3-O-glucoside, peonidin-3-O-glucoside, malvidin-3-O-glucoside, and cyanidin-3-O-glucoside dyes in aqueous solutions are reported. Following the addition of base to the flavylium cation, the quinoidal bases disappear by three distinct steps: (i) in an acidic medium by a biexponential process, in which the faster step is controlled by the hydration reaction and the slower one by cis-trans isomerization; the degradation process occurs essentially from the anionic quinoidal base; (ii) in a basic medium (pH > 9.5), in which the disappearance of the anionic bases is monoexponential, with the rate proportional to the hydroxyl concentration (hydroxyl attack), leading to anionic chalcones (cis and trans) at equilibrium─the slower degradation step occurs from the di- and trianionic chalcones; and (iii) in the pH region circa 7.7 < pH < 9.5, in which hydration and hydroxyl attacks are much slower than anionic quinoidal base degradation (which is the rate-controlling step) and the equilibrium cannot be attained.


Asunto(s)
Antocianinas , Chalcona , Concentración de Iones de Hidrógeno , Cinética , Termodinámica
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