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1.
Rom J Morphol Embryol ; 65(2): 273-278, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39020542

RESUMO

INTRODUCTION: The varicose vein affects more than 30% of the general population. Significantly increased rates were noticed in women and older population. From the histopathological point of view, venous arterialization, smooth muscle cell hypertrophy, and hyperplasia are the main changes noticed in varicose vein disease. Some of the main therapeutic methods used in the management of varicose disease are injection sclerotherapy, conservative, surgical, saphenous vein inversion and removal, high saphenous ligation, ambulatory phlebectomy, transilluminated powered phlebectomy, endovascular management, cryostripping. AIM: The aim of this study was to evaluate the morphology of connective fibers from the wall of the varicose veins extirpated by cryostripping. PATIENTS, MATERIALS AND METHODS: The study included 109 samples taken by cryostripping method. Hematoxylin-Eosin, Masson's trichrome, Silver and Orcein staining were applied. The assessment of fibers was made according to score values between 0 and 3. RESULTS: It was found no major structural differences in terms of alterations of collagen fibers induced by the applied surgical procedure. It was noticed duplications and multiplications of the internal elastic lamina, as diffuse and nodular forms. Depletion of elastic fibers at the media was a lesion identified in most of the specimens. The depletion of reticulin fibers correlates with the accumulation of collagen fibers, which partially or completely replace the network in the media and intima. No correlation was found between changes in the reticulin network and the time between prelevation and buffered formalin fixation, the maximum time investigated being five days. CONCLUSIONS: The Orcein staining in the venous vessel evaluation panel may be a useful investigation.


Assuntos
Varizes , Humanos , Varizes/cirurgia , Varizes/patologia , Feminino , Masculino , Pessoa de Meia-Idade , Tecido Conjuntivo/patologia , Adulto , Criocirurgia/métodos , Idoso
2.
Biomedicines ; 12(3)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38540090

RESUMO

BACKGROUND: Despite advancements in coronary artery bypass grafting (CABG), the optimal choice of graft material remains a subject of investigation. This study aimed to comprehensively analyze the morphological characteristics of varicose veins, exploring their potential utilization in CABG compared to healthy veins. METHODS: The study included 178 patients, categorized into two groups based on healthy and varicose veins. Morphological parameters, including maximum venous diameter, wall thickness, and specific changes in tunica intima (TI), tunica media (TM), and tunica adventitia (TA), were analyzed through microscopic evaluation. RESULTS: Varicose veins exhibited a significantly larger maximum venous diameter (p = 0.0001) and increased wall thickness (p = 0.0001) compared to healthy veins. Although varicose veins showed thickening in TI and TM, the differences were not statistically significant. Notably, disorganized smooth muscle bundles were more prevalent in varicose veins (p = 0.001), suggesting potential wall weakness. The absence of vasa vasorum in TA was significantly higher in varicose veins (p = 0.050), influencing vascularization considerations. CONCLUSIONS: The comparative morphological microscopic analysis of the specimens of healthy and varicose veins reveals significant differences between the groups, which make the conclusion of this study to plead for avoiding the use of varicose veins as a graft.

3.
Nat Commun ; 15(1): 1859, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424099

RESUMO

Studies suggest that inducing gut microbiota changes may alter both muscle physiology and cognitive behaviour. Gut microbiota may play a role in both anabolic resistance of older muscle, and cognition. In this placebo controlled double blinded randomised controlled trial of 36 twin pairs (72 individuals), aged ≥60, each twin pair are block randomised to receive either placebo or prebiotic daily for 12 weeks. Resistance exercise and branched chain amino acid (BCAA) supplementation is prescribed to all participants. Outcomes are physical function and cognition. The trial is carried out remotely using video visits, online questionnaires and cognitive testing, and posting of equipment and biological samples. The prebiotic supplement is well tolerated and results in a changed gut microbiome [e.g., increased relative Bifidobacterium abundance]. There is no significant difference between prebiotic and placebo for the primary outcome of chair rise time (ß = 0.579; 95% CI -1.080-2.239 p = 0.494). The prebiotic improves cognition (factor score versus placebo (ß = -0.482; 95% CI,-0.813, -0.141; p = 0.014)). Our results demonstrate that cheap and readily available gut microbiome interventions may improve cognition in our ageing population. We illustrate the feasibility of remotely delivered trials for older people, which could reduce under-representation of older people in clinical trials. ClinicalTrials.gov registration: NCT04309292.


Assuntos
Microbioma Gastrointestinal , Doenças Musculares , Idoso , Humanos , Envelhecimento , Cognição , Suplementos Nutricionais , Método Duplo-Cego , Microbioma Gastrointestinal/fisiologia , Músculos , Pessoa de Meia-Idade
4.
Diabetes ; 72(12): 1870-1880, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37699401

RESUMO

Prediabetes is a metabolic condition associated with gut microbiome composition, although mechanisms remain elusive. We searched for fecal metabolites, a readout of gut microbiome function, associated with impaired fasting glucose (IFG) in 142 individuals with IFG and 1,105 healthy individuals from the UK Adult Twin Registry (TwinsUK). We used the Cooperative Health Research in the Region of Augsburg (KORA) cohort (318 IFG individuals, 689 healthy individuals) to replicate our findings. We linearly combined eight IFG-positively associated metabolites (1-methylxantine, nicotinate, glucuronate, uridine, cholesterol, serine, caffeine, and protoporphyrin IX) into an IFG-metabolite score, which was significantly associated with higher odds ratios (ORs) for IFG (TwinsUK: OR 3.9 [95% CI 3.02-5.02], P < 0.0001, KORA: OR 1.3 [95% CI 1.16-1.52], P < 0.0001) and incident type 2 diabetes (T2D; TwinsUK: hazard ratio 4 [95% CI 1.97-8], P = 0.0002). Although these are host-produced metabolites, we found that the gut microbiome is strongly associated with their fecal levels (area under the curve >70%). Abundances of Faecalibacillus intestinalis, Dorea formicigenerans, Ruminococcus torques, and Dorea sp. AF24-7LB were positively associated with IFG, and such associations were partially mediated by 1-methylxanthine and nicotinate (variance accounted for mean 14.4% [SD 5.1], P < 0.05). Our results suggest that the gut microbiome is linked to prediabetes not only via the production of microbial metabolites but also by affecting intestinal absorption/excretion of host-produced metabolites and xenobiotics, which are correlated with the risk of IFG. Fecal metabolites enable modeling of another mechanism of gut microbiome effect on prediabetes and T2D onset. ARTICLE HIGHLIGHTS: Prediabetes is a metabolic condition associated with gut microbiome composition, although mechanisms remain elusive. We investigated whether there is a fecal metabolite signature of impaired fasting glucose (IFG) and the possible underlying mechanisms of action. We identified a fecal metabolite signature of IFG associated with prevalent IFG in two independent cohorts and incident type 2 diabetes in a subanalysis. Although the signature consists of metabolites of nonmicrobial origin, it is strongly correlated with gut microbiome composition. Fecal metabolites enable modeling of another mechanism of gut microbiome effect on prediabetes by affecting intestinal absorption or excretion of host compounds and xenobiotics.


Assuntos
Diabetes Mellitus Tipo 2 , Niacina , Estado Pré-Diabético , Adulto , Humanos , Estado Pré-Diabético/complicações , Diabetes Mellitus Tipo 2/complicações , Jejum , Glucose , Glicemia/metabolismo
5.
Gut Microbes ; 15(1): 2240050, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37526398

RESUMO

Short-chain fatty acids (SCFA) are involved in immune system and inflammatory responses. We comprehensively assessed the host genetic and gut microbial contribution to a panel of eight serum and stool SCFAs in two cohorts (TwinsUK, n = 2507; ZOE PREDICT-1, n = 328), examined their postprandial changes and explored their links with chronic and acute inflammatory responses in healthy individuals and trauma patients. We report low concordance between circulating and fecal SCFAs, significant postprandial changes in most circulating SCFAs, and a heritable genetic component (average h2: serum = 14%(SD = 14%); stool = 12%(SD = 6%)). Furthermore, we find that gut microbiome can accurately predict their fecal levels (AUC>0.71) while presenting weaker associations with serum. Finally, we report different correlation patterns with inflammatory markers depending on the type of inflammatory response (chronic or acute trauma). Our results illustrate the breadth of the physiological relevance of SCFAs on human inflammatory and metabolic responses highlighting the need for a deeper understanding of this important class of molecules.


Assuntos
Microbioma Gastrointestinal , Humanos , Microbioma Gastrointestinal/genética , Ácidos Graxos Voláteis/metabolismo , Fezes , Inflamação
6.
Materials (Basel) ; 16(7)2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-37048844

RESUMO

Chemical-mechanical planarization (CMP) represents the preferred technology in which both chemical and mechanical interactions are combined to achieve global planarization/polishing of wafer surfaces (wafer patterns from metal with a selective layer, in this paper). CMP is a complex process of material removal process by friction, which interferes with numerous mechanical and chemical parameters. Compared with chemical parameters, mechanical parameters have a greater influence on the material removal rate (MRR). The mechanical parameters manifest by friction force (Ff) and heat generated by friction in the CMP process. The Ff can be estimated by its monitoring in the CMP process, and process temperature is obtained with help of an infrared rays (IR) sensor. Both the Ff and the MRR increase by introducing colloidal silica (SiO2) as an abrasive into the selective layer CMP slurry. The calculated wafer non-uniformity (WNU) was correlated with the friction coefficient (COF). The control of Ff and of the slurry stability is important to maintain a good quality of planarization with optimal results, because Ff participates in mechanical abrasion, and large Ff may generate defects on the wafer surface. Additionally, the temperature generated by the Ff increases as the SiO2 concentration increases. The MRR of the selective layer into the CMP slurry showed a non-linear (Prestonian) behavior, useful not only to improve the planarization level but to improve its non-uniformity due to the various pressure distributions. The evaluation of the Ff allowed the calculation of the friction energy (Ef) to highlight the chemical contribution in selective-layer CMP, from which it derived an empirical model for the material removal amount (MRA) and validated by the CMP results. With the addition of abrasive nanoparticles into the CMP slurry, their concentration increased and the MRA of the selective layer improved; Ff and MRR can be increased due to the number of chemisorbed active abrasive nanoparticles by the selective layer. Therefore, a single abrasive was considered to better understand the effect of SiO2 concentration as an abrasive and of the MRR features depending on abrasive nanoparticle concentration. This paper highlights the correlation between friction and temperature of the SiO2 slurry with CMP results, useful to examine the temperature distribution. All the MRRs depending on Ef after planarization with various SiO2 concentrations had a non-linear characteristic. The obtained results can help in developing a CMP process more effectively.

7.
Cell Rep Med ; 4(4): 100993, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37023745

RESUMO

Primary and secondary bile acids (BAs) influence metabolism and inflammation, and the gut microbiome modulates levels of BAs. We systematically explore the host genetic, gut microbial, and habitual dietary contribution to a panel of 19 serum and 15 stool BAs in two population-based cohorts (TwinsUK, n = 2,382; ZOE PREDICT-1, n = 327) and assess changes post-bariatric surgery and after nutritional interventions. We report that BAs have a moderately heritable genetic component, and the gut microbiome accurately predicts their levels in serum and stool. The secondary BA isoursodeoxycholate (isoUDCA) can be explained mostly by gut microbes (area under the receiver operating characteristic curve [AUC] = ∼80%) and associates with post-prandial lipemia and inflammation (GlycA). Furthermore, circulating isoUDCA decreases significantly 1 year after bariatric surgery (ß = -0.72, p = 1 × 10-5) and in response to fiber supplementation (ß = -0.37, p < 0.03) but not omega-3 supplementation. In healthy individuals, isoUDCA fasting levels correlate with pre-meal appetite (p < 1 × 10-4). Our findings indicate an important role for isoUDCA in lipid metabolism, appetite, and, potentially, cardiometabolic risk.


Assuntos
Cirurgia Bariátrica , Ácidos e Sais Biliares , Humanos , Apetite , Cirurgia Bariátrica/efeitos adversos , Fezes , Inflamação
8.
Materials (Basel) ; 16(4)2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36837372

RESUMO

Composites based on poly(3,4-ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT:PSS)-graphene oxide (GO) are increasingly considered for sensing applications. In this work we aim at patterning and prototyping microscale geometries of PEDOT:PSS: GO composites for the modification of commercially available electrochemical sensors. Here, we demonstrate the laser-induced forward transfer of PEDOT:PSS: GO composites, a remarkably simple procedure that allows for the fast and clean transfer of materials with high resolution for a wide range of laser fluences (450-750 mJ/cm2). We show that it is possible to transfer PEDOT:PSS: GO composites at different ratios (i.e., 25:75 %wt and 50:50 %wt) onto flexible screen-printed electrodes. Furthermore, when testing the functionality of the PEDOT:PSS: GO modified electrodes via LIFT, we could see that both the PEDOT:PSS: GO ratio as well as the addition of an intermediate release layer in the LIFT process plays an important role in the electrochemical response. In particular, the ratio of the oxidation peak current to the reduction peak current is almost twice as high for the sensor with a 50:50 %et PEDOT:PSS: GO pixel. This direct transfer methodology provides a path forward for the prototyping and production of polymer: graphene oxide composite based devices.

9.
Nanomaterials (Basel) ; 12(7)2022 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-35407255

RESUMO

This work is focused on the application of a laser-based technique, i.e., matrix-assisted pulsed laser evaporation (MAPLE) for the development of electrochemical sensors aimed at the detection of nitrites in water. Commercial carbon-based screen-printed electrodes were modified by MAPLE via the application of a newly developed composite coating with different concentrations of carbon nanotubes (CNTs), chitosan, and iron (II) phthalocyanine (C32H16FeN8). The performance of the newly fabricated composite coatings was evaluated both by investigating the morphology and surface chemistry of the coating, and by determining the electro-catalytic oxidation properties of nitrite with bare and modified commercial carbon-based screen-printed electrode. It was found that the combined effect of CNTs with chitosan and C32H16FeN8 significantly improves the electrochemical response towards the oxidation of nitrite. In addition, the MAPLE modified screen-printed electrodes have a limit of detection of 0.12 µM, which make them extremely useful for the detection of nitrite traces.

10.
Materials (Basel) ; 15(7)2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35407822

RESUMO

In this work, we report the modification of commercially available electrochemical electrodes with tin oxide (SnO2) and Pd doped SnO2 (Pd-SnO2) via pulsed laser-induced forward transfer (LIFT). The pulsed light irradiation working as in situ pulsed photo-thermal treatment allows for the transfer of SnO2 and Pd-SnO2 from UV absorbing metal complex precursors onto flexible, commercially available screen-printed electrodes. The laser transfer conditions are optimized and the material transferred under different conditions is evaluated morphologically and chemically, and its functionality is tested against the detection of copper ions. For example, by applying laser fluences in the range 100-250 mJ/cm2, the shape and the size of the transferred features ranges from nano-polyhedrons to near corner-grown cubic Pd-SnO2 or near cubic Pd-SnO2. In addition, the EDX analysis is consistent with the XPS findings, i.e., following laser transfer, Pd amounts lower than 0.5% are present in the Pd-SnO2 pixels. First sensing tests were carried out and the transferred Pd-SnO2 proved to enhance the cathodic peak when exposed to Cu(II) ions. This photo-initiated fabrication technology opens a promising way for the low-cost and high-throughput manufacturing of metal oxides as well as for electrodes for heavy metal ion detection.

11.
Nanomaterials (Basel) ; 12(3)2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-35159894

RESUMO

In this work, thin films of lamellar clays were deposited by laser techniques (matrix assisted pulsed laser evaporation (MAPLE) and pulsed laser deposition (PLD)). The focus of this paper is the optimization of deposition parameters for the production of highly oriented crystalline films. The films were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and scanning electron microscopy (SEM). Contact angle measurements were employed to identify the wetting properties of the deposited thin films. Hydrophobic to superhydrophilic films can be prepared by using different deposition techniques and deposition parameters. MAPLE led to superhydrophilic films with contact angles in the range 4°-8°, depending on the microstructure and surface roughness at micro and nano scale. The 1064 nm PLD had a high deposition rate and produced a textured film while at λ = 193 nm an extremely thin and amorphous layer was depicted. Oriented kaolinite films were obtained by MAPLE even at 5 wt.% kaolinite in the target.

12.
Diagnostics (Basel) ; 11(11)2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34829306

RESUMO

BACKGROUND: The primary endpoint was to analyze the preoperatory inflammatory markers and platelet indices in papillary thyroid cancer (PTC) patients compared with patients with benign thyroid pathology. The secondary endpoints were to analyze the relationship between these markers and the pathological features of PTC and to compare their pre- and postoperative levels in PTC patients. METHODS: In this retrospective case-control study, we analyzed the files of 1183 patients submitted to thyroidectomy between January 2012 and December 2018. A total of 234 patients with PTC (mean age 51.54 ± 13.10 years, 84.6% females) were compared with an age-, gender- and BMI-matched control group of 108 patients with histologic benign thyroid disorders. RESULTS: PTC patients had higher platelet count (PLT) (p = 0.011), plateletcrit (PCT) (p = 0.006), neutrophil (p = 0.022) and fibrinogen (p = 0.005) levels. Subgroup analysis showed that PTC females had higher PLT (p = 0.006), PCT (p < 0.001) and erythrocyte sedimentation rate (ESR) (p = 0.005), while males had higher neutrophil (p = 0.040) levels. Papillary thyroid cancer patients under 55 years had higher PLT (p < 0.001) and PCT (p = 0.010), while patients over 55 years had higher mean platelet volume (p = 0.032), neutrophil-to-lymphocyte ratio (p = 0.013), ESR (p = 0.005) and fibrinogen (p = 0.019) levels. Preoperative values for platelet indices and inflammatory markers were similar to the postoperative determinations in PTC patients. Fibrinogen (AUROC = 0.602, p = 0.02; cut-off = 327.5 mg/dL, Se = 53.8%, Sp = 62.9%) and PLT (AUROC = 0.584, p = 0.012; cut-off = 223.5 × 103/mm3, Se = 73.1%, Sp = 42.6%) were independent predictors of the presence of PTC. CONCLUSIONS: Our data show that fibrinogen and platelet count could be promising, inexpensive, independent predictors for the presence of PTC when compared with benign thyroid disorders.

13.
J Crit Care Med (Targu Mures) ; 7(2): 141-144, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34722916

RESUMO

Recent randomized controlled trials have transformed the treatment of acute ischemic stroke. Mechanical or aspiration thrombectomy is the main treatment option for occlusions of large intracranial vessels. Despite its high technical success rate, endovascular thrombectomy can sometimes be complicated by anatomical peculiarities or device failures. The most frequent complications are related to vessel dissection or vessel perforation by devices while navigating intricate anatomy. Rarer still are technical device failures, like spontaneous stent-retriever detachment, which occurred with older generation retrievers. This case reports a rare device failure, which, to the best of our knowledge, has not been reported in the literature so far, namely a microwire fracture in the middle cerebral artery. This was successfully removed with an Eric stent-retriever. The potential causes and possible management strategies are discussed.

14.
BMC Geriatr ; 21(1): 407, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34210274

RESUMO

BACKGROUND: Loss of skeletal muscle mass and strength occurs with increasing age and is associated with loss of function, disability, and the development of sarcopenia and frailty. Dietary protein is essential for skeletal muscle function, but older adults do not anabolise muscle in response to protein supplementation as well as younger people, so called 'anabolic resistance'. The aetiology and molecular mechanisms for this are not understood, however the gut microbiome is known to play a key role in several of the proposed mechanisms. Thus, we hypothesise that the gut microbiome may mediate anabolic resistance and therefore represent an exciting new target for ameliorating muscle loss in older adults. This study aims to test whether modulation of the gut microbiome using a prebiotic, in addition to protein supplementation, can improve muscle strength (as measured by chair-rise time) versus protein supplementation alone. METHODS: The study is a randomised, double-blinded, placebo-controlled trial, with two parallel arms; one will receive prebiotic and protein supplementation, and the other will receive placebo (maltodextrin) and protein supplementation. Participants will be randomised as twin pairs, with one twin from each pair in each arm. Participants will be asked to take supplementation once daily for 12 weeks in addition to resistance exercises. Every participant will receive a postal box, containing their supplements, and the necessary equipment to return faecal, urine, saliva and capillary blood samples, via post. A virtual visit will be performed using online platform at the beginning and end of the study, with measures taken over video. Questionnaires, food diary and cognitive testing will be sent out via email at the beginning and end of the study. DISCUSSION: This study aims to provide evidence for the role of the gut microbiome in anabolic resistance to dietary protein. If those who take the prebiotic and protein supplementation have a greater improvement in muscle strength compared with those who take protein supplementation alone, this would suggest that strategies to modify the gut microbiome may reduce anabolic resistance, and therefore potentially mitigate sarcopenia and frailty in older adults. TRIAL REGISTRATION: Clinicaltrials.gov: NCT04309292 . Registered on the 2nd May 2020.


Assuntos
Microbioma Gastrointestinal , Sarcopenia , Idoso , Suplementos Nutricionais , Método Duplo-Cego , Humanos , Força Muscular , Prebióticos , Ensaios Clínicos Controlados Aleatórios como Assunto , Sarcopenia/tratamento farmacológico , Sarcopenia/prevenção & controle
15.
Nanomaterials (Basel) ; 11(6)2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34064298

RESUMO

Tuning the intrinsic structural and stoichiometric properties by different means is used for increasing the green energy production efficiency of complex oxide materials. Here, we report on the formation of self-assembled nanodomains and their effects on the photoelectrochemical (PEC) properties of LaFeO3 (LFO) epitaxial thin films as a function of layer's thickness. The variation with the film's thickness of the structural parameters such as in-plane and out-of-plane crystalline coherence length and the coexistence of different epitaxial orientation-<100>SrTiO3//<001> LFO, <100>SrTiO3//<110> LFO and [110] LFO//[10] STO, as well as the appearance of self-assembled nanodomains for film's thicknesses higher than 14 nm, is presented. LFO thin films exhibit different epitaxial orientations depending on their thickness, and the appearance of self-assembled nanopyramids-like domains after a thickness threshold value has proven to have a detrimental effect on the PEC functional properties. Using Nb:SrTiO3 as conductive substrate and 0.5 M NaOH aqueous solution for PEC measurements, the dependence of the photocurrent density and the onset potential vs. RHE on the structural and stoichiometric features exhibited by the LFO photoelectrodes are unveiled by the X-ray diffraction, high-resolution transmission electron microscopy, ellipsometry, and Rutherford backscattering spectroscopy results. The potentiodynamic PEC analysis has revealed the highest photocurrent density Jphotocurrent values (up to 1.2 mA/cm2) with excellent stability over time, for the thinnest LFO/Nb:SrTiO3 sample, both cathodic and anodic behavior being noticed. Noticeably, the LFO thin film shows unbiased hydrogen evolution from water, as determined by gas chromatography in aqueous 0.5 M NaOH solution under constant illumination.

16.
Nanomaterials (Basel) ; 11(1)2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33418853

RESUMO

Due to its physical and chemical properties, the n-type tungsten oxide (WO3) semiconductor is a suitable photoanode for water decomposition reaction. The responses of the photoelectrochemical PEC water-splitting properties as an effect of structural and optical changes of WO3 thin films, as well as the nature of electrolyte solutions, were studied in this work. The WO3 thins films have been obtained by pulsed laser deposition (PLD) on silicon (Si(001)) covered with platinum substrates using three different laser wavelengths. As the XRD (X-ray diffraction) and XTEM (cross-section transmission electron microscopy) analysis shows, the formation of highly crystalline monocline WO3 phase is formed for the film deposited at 1064 nm wavelength and poor crystalline phases with a large ordering anisotropy, characteristic of 2D structures for the films deposited at 355 nm and 193 nm wavelengths, respectively. The photogenerated current densities Jph depend on the laser wavelength, in both alkaline and acidic electrolyte. The maximum values of the photocurrent density have been obtained for the sample prepared with laser emitting at 355 nm. This behavior can be correlated with the coherent crystallized atomic ordering that appear for long distances (10-15 nm) in the (001) plane of the monoclinic WO3 phase structure films obtained at 355 nm laser wavelength. All the samples show poor current density in dark conditions and they are very stable in both acidic and alkaline solutions. The highest photocurrent density value is obtained in acidic solution for the WO3 thin film prepared by 355 nm laser (29 mA/cm2 at 1.6 V vs. RHE (1.35 V vs. Ag/AgCl)).

17.
Rheumatology (Oxford) ; 60(8): 3727-3737, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-33331911

RESUMO

OBJECTIVES: Chronic widespread musculoskeletal pain (CWP) is a characteristic symptom of fibromyalgia, which has been shown to be associated with an altered gut microbiome. Microbiome studies to date have not examined the milder CWP phenotype specifically nor have they explored the role of raised BMI. The aim of this study was to investigate whether the microbiome is abnormal in CWP. METHODS: CWP was assessed using a standardized screening questionnaire in female volunteers from the TwinsUK cohort including 113 CWP cases and 1623 controls. The stool microbiome was characterized using 16S rRNA amplicon sequencing and amplicon sequence variants, and associations with CWP examined using linear mixed-effects models adjusting for BMI, age, diet, family relatedness and technical factors. RESULTS: Alpha diversity was significantly lower in CWP cases than controls (Mann-Whitney test, P-values 2.3e-04 and 1.2e-02, for Shannon and Simpson indices respectively). The species Coprococcus comes was significantly depleted in CWP cases (Padj = 3.04e-03). A genome-wide association study (GWAS) performed for C. comes in TwinsUK followed by meta-analysis with three Dutch cohorts (total n = 3521) resulted in nine suggestive regions, with the most convincing on chromosome 4 near the TRAM1L1 gene (rs76957229, P = 7.4e-8). A Mendelian randomization study based on the results of the GWAS did not support a causal role for C. comes on the development of CWP. CONCLUSIONS: We have demonstrated reduced diversity in the microbiome in CWP, indicating an involvement of the gut microbiota in CWP; prospectively the microbiome may offer therapeutic opportunities for this condition.


Assuntos
Dor Crônica/epidemiologia , Disbiose/epidemiologia , Microbioma Gastrointestinal/genética , Idoso , Índice de Massa Corporal , Dor Crônica/genética , Dor Crônica/microbiologia , Clostridiales , Disbiose/genética , Disbiose/microbiologia , Feminino , Humanos , Análise da Randomização Mendeliana , Pessoa de Meia-Idade , Obesidade/epidemiologia , Obesidade/microbiologia , RNA Ribossômico 16S
18.
Materials (Basel) ; 13(23)2020 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-33291516

RESUMO

This review paper focuses on perovskite-type materials as (photo)catalysts for energy and environmental applications. After a short introduction and the description of the structure of inorganic and hybrid organic-inorganic perovskites, the methods of preparation of inorganic perovskites both as powders via chemical routes and as thin films via laser-based techniques are tackled with, for the first, an analysis of the influence of the preparation method on the specific surface area of the material obtained. Then, the (photo)catalytic applications of the perovskites in energy production either in the form of hydrogen via water photodecomposition or by methane combustion, and in the removal of organic pollutants from waste waters, are reviewed.

19.
Chirurgia (Bucur) ; 114(5): 602-610, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31670636

RESUMO

Background: Post-surgical hypoparathyroidism (PoSH) is a common long-term complication after thyroid surgery. The reported median (range) incidence rates of temporary and permanent PoSH was 27% (19 - 38%) and 1% (0 - 3%) respectively. Material and Methods: We retrospectively analyzed the files of 552 patients who underwent thyroidectomy in our surgery department between 2015- 2017 with the aim to assess the prevalence of PoSH and to identify patient and disease related factors associated with postoperative hypocalcemia. Results: 171 (30.97%) patients developed PoSH, 88.37% transient, 11.63% permanent. The median (IQR) duration of postoperative hypocalcemia was 60 (67.5) days. Preoperative biological parameters were similar in PoSH and the control group, except median (IQR) serum magnesium level that was significantly higher in PoSH group [2.04 (0.17) vs. 1.89 (0.28) mg/dl, p=0.005]. In the subgroup of patients with thyroid carcinoma the surgery duration was longer in PoSH patients compared to the control group [135 (60) vs. 110 (43) minutes, p=0.020]. In patients with PoSH, median post-operative serum calcium was significantly higher in patients with reported difficult surgery [8.2 (0.2) vs. 7.9 (0.6) mg/dl, p=0.043] and the mean serum calcium decrease was higher in patients with cervical neck dissection and lymphadenectomy (1.94 +-0.59 vs. 1.68 +-0.56 mg/dl, p=0.033). Conclusions: Our data show a high prevalence of PoSH that is likely to increase given the rising number of thyroid surgeries being performed. Further research is needed in order to better define this condition, to establish appropriate treatment and preventive measures.


Assuntos
Hipoparatireoidismo/etiologia , Tireoidectomia/efeitos adversos , Humanos , Hipocalcemia/sangue , Hipoparatireoidismo/sangue , Estudos Retrospectivos , Tireoidectomia/métodos
20.
Bioelectrochemistry ; 129: 124-134, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31158797

RESUMO

The antioxidant properties of different plant extracts are usually claimed and used by food, medicine and cosmetic industry due to their health promoting capacities. In this study the presence of antioxidant compounds and the total antioxidant capacity of water-soluble extracts, prepared using two extraction methods and a variety of solvents, have been determined and a rapid screening method has been developed. Plant extracts characterisation, composition and antioxidant properties were confirmed by FTIR and Raman spectroscopies. Voltammetry, amperometry and electrochemical impedance were used to highlight the total antioxidant capacity of each extract using an electrochemical gold nanozyme-sensor based on the enzyme-like catalytic activity of gold nanoparticles. Both anodic area of cyclic voltammograms (10.31 µA V) and electrochemical index (153) calculated using differential potential voltammetry show the total content of antioxidant compounds, allowing to discriminate between different extracts. Amperometric total antioxidant capacity measurements were associated with those from classical chemiluminescence and good correlation has been found (Pearson's correlation coefficient of 0.958).


Assuntos
Antioxidantes/química , Técnicas Eletroquímicas/métodos , Ouro/química , Hippophae/química , Lavandula/química , Nanopartículas Metálicas/química , Extratos Vegetais/química , Antioxidantes/farmacologia , Técnicas Biossensoriais/métodos , Espectroscopia Dielétrica , Peróxido de Hidrogênio/química , Extratos Vegetais/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
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