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Iodine is a trace element required to produce the thyroid hormones, which are critical for development, growth and metabolism. To ensure appropriate population iodine nutrition, convenient and accurate methods of monitoring are necessary. Current methods for determining iodine status either involve a significant participant burden or are subject to considerable intra-individual variation. The continuous secretion of iodide in saliva potentially permits its use as a convenient, non-invasive assessment of status in populations. To assess its likely effectiveness, we reviewed studies analysing the association between salivary iodide concentration (SIC) and dietary iodine intake, urinary iodide concentration (UIC) and/or 24-h urinary iodide excretion (UIE). Eight studies conducted in different countries met the inclusion criteria, including data for 921 subjects: 702 healthy participants and 219 with health conditions. SIC correlated positively with UIC and/or UIE in four studies, with the strength of relationship ranging from r = 0·19 to r = 0·90 depending on sampling protocol, age, and if salivary values were corrected for protein concentration. Additionally, SIC positively correlated with dietary intake, being strongest when saliva was collected after dinner. SIC varied with external factors, including thyroid function, use of some medications, smoking and overall health status. Evidence provided here supports the use of SIC as a viable, low-burden method for determining iodine status in populations. However, small sample sizes and high variability indicates the need for more extensive analyses across age groups, ethnicities, disease states and dietary groups to clarify the relative accuracy and reliability in each case and standardise procedure.
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Homeostase , Iodetos , Iodo , Estado Nutricional , Saliva , Humanos , Iodo/análise , Iodo/urina , Saliva/química , Saliva/metabolismo , Iodetos/análise , Iodetos/metabolismo , Feminino , Dieta , Masculino , Adulto , Pessoa de Meia-Idade , IdosoRESUMO
A healthy breath is mainly composed of water, carbon dioxide, molecular nitrogen, and oxygen and it contains many species, in small quantities, which are related to the ambient atmosphere and the metabolism. The breath of a person affected by lung cancer presents a concentration of 1-propanol higher than usual. In this context, the development of specific sensors to detect 1-propanol from breath is of high interest. The amount of propanol usually detected on the breath is of few ppb; this small quantity is a handicap for a reliable diagnostic. This limitation can be overcome if the sensor is equipped with a pre-concentrator. Our studies aim to provide an efficient material playing this role. This will contribute to the development of reliable and easy to use lung cancer detectors. For this, we investigate the properties of a few hydrophobic porous materials (chabazite, silicalite-1, and dealuminated faujasite). Hydrophobic structures are used to avoid saturation of materials by the water present in the exhaled breath. Our experimental and simulation results suggest that silicalite -1 (MFI) is the most suitable structure to be used as a pre-concentrator.
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Neoplasias Pulmonares , Zeolitas , Humanos , 1-Propanol , Adsorção , Neoplasias Pulmonares/diagnóstico , Zeolitas/química , Água/químicaRESUMO
The unique properties of zeolites make them an interesting material to be used in separation processes. The possibility of tailoring some of their characteristics, like the Si/Al ratio, allows optimizing their synthesis for a given task. Concerning the adsorption of toluene by faujasites an understanding of the effect of cations is necessary to foster the elaboration of new materials, which can capture molecules with a high degree of selectivity and sensitivity. Undoubtedly, this knowledge is relevant for a wide range of applications going from the elaboration of technologies for improving the air-quality to diagnostic procedures to prevent health risks. The studies reported here using Grand Canonical Monte Carlo simulations elucidate the role of Na-cations in the adsorption of toluene by faujasites with different Si/Al ratios. They detail how the location of the cations inhibits or enhances the adsorption. The cations located at site II are shown to be those enhancing the adsorption of toluene on faujasites. Interestingly, the cations located at site III generate a hindrance at high loading. This becomes an impediment for the organization of toluene molecules inside faujasites.
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Vegan and vegetarian diets are widely supported and adopted, but individuals following such diets remain at greater risk of iodine deficiency. This systematic review and meta-analysis was conducted to assess the iodine intake and status in adults following a vegan or vegetarian diet in the modern day. A systematic review and quality assessment were conducted from October 2020 to December 2022 according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and Meta-analysis of Observational Studies in Epidemiology (MOOSE) guidance. Studies were identified in Ovid MEDLINE, Web of Science, PubMed, and Scopus. Eleven articles were eligible for review containing 4421 adults (aged ≥ 18 years). Vegan groups had the lowest median urinary iodine concentration (mUIC) (12·2/l). None of the dietary groups had mUIC within the optimal range for iodine status (100-200 µg/l) (WHO). Vegan diets had the poorest iodine intake (17·3 µg/d) and were strongly associated with lower iodine intake (P = < 0·001) compared with omnivorous diets. Lower intake in vegan diets was influenced by sex (P = 0·007), the presence of voluntary or absence of Universal Salt Iodisation (USI) programmes (P = 0·01 & P = < 0·001), and living in a country with adequate iodine nutrition (P = < 0·001). Vegetarians and particularly vegans living in countries with no current USI programme continue to have increased risk of low iodine status, iodine deficiency and inadequate iodine intake. Further research into the usefulness of mandatory fortification of vegan appropriate foods is required.
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Dieta Vegana , Iodo , Adulto , Humanos , Veganos , Dieta Vegetariana , Estado Nutricional , VegetarianosRESUMO
PURPOSE: The aim of the present retrospective study was to report outcomes after hypofractionated stereotactic radiotherapy (HSRT) for resected brain metastases (BM). PATIENTS AND METHODS: We reviewed results of patients with resected BM treated with postoperative HSRT (3×7.7Gy to the prescription isodose 70%) between May 2013 and June 2020. Local control (LC), distant brain control (DBC), overall survival (OS), leptomeningeal disease relapse (LMDR), and radiation necrosis (RN) occurrence were reported. RESULTS: Twenty-two patients with 23 brain cavities were included. Karnofsky Performance status (KPS) was≥70 in 77.3%. Median preoperative diameter was 37mm [21.0-75.0] and median planning target volume (PTV) was 23 cm3 [9.9-61.6]. Median time from surgery to SRT was 69 days [7-101] and 48% of patients had a local relapse on pre-SRT imaging. Median follow-up was 17.5 months [1.6-95.9]. One and two-year LC rates were 60.9 and 52.2% respectively. One and 2-year DBC rates were 45.5 and 40.9%. Median OS was 16.5 months. Four patients (18.2%) presented LMDR during follow-up. RN occurred in 6 patients (27.2%). Three factors were associated with OS: ECOG-PS (P=0.009), KPS (P=0.04), cystic or solid nature of the metastasis before surgery (P=0.037). Several factors were related to RN occurrence: PTV diameter and volume, Normal brain V21, V21 and V24 isodoses volumes. CONCLUSION: HSRT is the most widely used scheme for larger brain cavities after surgery. The optimal dose and scheme remain to be defined as well as the optimal delay between postoperative SRT and surgery. Dose escalation may be necessary, especially in case of subtotal resection.
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Neoplasias Encefálicas , Radiocirurgia , Humanos , Estudos Retrospectivos , Seguimentos , Recidiva Local de Neoplasia/patologia , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirurgia , Neoplasias Encefálicas/secundário , Encéfalo/patologia , Radiocirurgia/métodos , Resultado do TratamentoRESUMO
INTRODUCTION: Worldwide more and more primary knee replacements are being performed. Kinematic alignment (KA) as one of many methods of surgical alignment has been shown to have a significant impact on kinematics and function. The aim of the present study was to compare KA and mechanical alignment (MA) with regard to femorotibial kinematics. MATERIALS AND METHODS: Eight fresh frozen human specimens were tested on a knee rig during active knee flexion from 30 to 130°. Within the same specimen a medial stabilized (MS) implant design was used first with KA and then with MA. RESULTS: The femorotibial kinematics showed more internal rotation of the tibia in KA compared to MA. At the same time, there was a larger medial rotation point in KA. Both alignment methods showed femoral rollback over the knee bend. CONCLUSION: Relating to an increased internal rotation and a more precise medial pivot point, it can be concluded that KA combined with a MS implant design may partially support the reproduction of physiological knee joint mechanics.
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Artroplastia do Joelho , Prótese do Joelho , Osteoartrite do Joelho , Humanos , Artroplastia do Joelho/métodos , Fenômenos Biomecânicos , Amplitude de Movimento Articular/fisiologia , Cadáver , Articulação do Joelho , Osteoartrite do Joelho/cirurgiaRESUMO
The Kirkwood-Buff theory is a cornerstone of the statistical mechanics of liquids and solutions. It relates volume integrals over the radial distribution function, so-called Kirkwood-Buff integrals (KBIs), to particle number fluctuations and thereby to various macroscopic thermodynamic quantities such as the isothermal compressibility and partial molar volumes. Recently, the field has seen a strong revival with breakthroughs in the numerical computation of KBIs and applications to complex systems such as bio-molecules. One of the main emergent results is the possibility to use the finite volume KBIs as a tool to access finite volume thermodynamic quantities. The purpose of this Perspective is to shed new light on the latest developments and discuss future avenues.
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Soluções , TermodinâmicaRESUMO
PURPOSE: Management of inter- and intra-fraction movements of target volumes and organs at risk (OARs) during radiotherapy is essential. While there is little OAR or target volume movement, the movements and orientation of the eyes can be significant during radiotherapy and they can affect the position of the optic nerve. The objective of the present study was to assess the variations of the optic nerve position due to gaze direction and to discuss their clinical consequences on the radiation treatment of intraorbital tumors. MATERIAL AND METHODS: Three patients without a history of oculomotor nerve palsy underwent six CT acquisitions with a thermoplastic mask: eyes open with different gaze directions (straight ahead, left, right, up, down) and eyes closed. The acquisition with the straight-ahead gaze was chosen as the reference position. Left and right optic nerves were segmented on the six acquisitions, and total volumes and maximum amplitude motions were calculated in three dimensions. RESULTS: Maximum differences were observed while looking left and up, with a median maximum amplitude of 5 and 6mm [range: 2-7mm], respectively. These motions induced a position variation of more than 50% of the volume of the optic nerve (compared to the reference position). Greater variations of motion were observed for the anterior portion of the nerve. The gaze position with the fewest variations compared to the reference position was eyes closed. CONCLUSION: Optic nerve positions vary significantly due to the gaze direction, especially for the anterior portion of the nerve. These variations should be taken into account for the treatment of small intraorbital tumors involving the anterior third of the optic nerve.
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Neoplasias , Radioterapia (Especialidade) , Humanos , Movimento (Física) , Movimento/fisiologia , Nervo Óptico/diagnóstico por imagemRESUMO
Radiation therapy (RT) is one of the main treatments administered to patients with cancer. The development of technology has improved RT accuracy by allowing more precise delivery of high doses to the target volumes with reduced exposure of healthy tissue. Life expectancy has increased due to these therapeutic advancements and the patients' quality of life remains a major concern. The adverse events related to RT are quite various and most likely will impair essential neurological functions, e.g. cognitive status. This literature review aims to describe the physiopathological processes, the neurological symptoms as well as the local modifications observed in magnetic resonance imaging following RT. The specific therapeutic options and preventive actions will also be discussed.
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Neoplasias , Qualidade de Vida , Humanos , Imageamento por Ressonância MagnéticaRESUMO
We test whether vegetation community composition from a 10-year climate manipulation experiment on a Welsh peat bog resembles vegetation communities during periods of climate change inferred from a peat core. Experimentally warmed and combined warmed and droughted treatments drove significant increases in ericaceous shrubs but Sphagnum was unaffected. Similarly, Calluna vulgaris seeds increase during inferred warmer periods in the palaeoecological record. Experimental short-term episodic drought (four 4-week drought treatments) did not affect vegetation. Plant community composition has undergone several abrupt changes throughout the past c. 1500 years, often in response to human disturbance. Only slight changes occurred during the Medieval Climate Anomaly (c. 950-1250 Common Era [CE]) in vegetation and hydrology, while abrupt changes occurred during the Little Ice Age (c. 1300-1850 CE) when water tables were highest, suggesting that these shifts were driven by changes in water table, modulated by climate. A period of water table drawdown c. 1800, synchronous with historical records of increased drainage, corresponds with the development of the present-day vegetation community. Modern analogues for fossil material, characterized by abundant Rhynchospora alba and Sphagnum pulchrum, are more common after this event. Vegetation changes due to climate inferred from the palaeo record differ from those observed in the experiments, possibly relating to differences in the importance of drivers of vegetation change over varying timescales. Whereas temperature is frequently identified as the dominant driver of plant community change in experiments, sustained changes in water table appear to be more important in the long-term record. We find evidence that recent climate change and other anthropogenic stressors (e.g. drainage, heavy metal and nitrogen pollution) may promote the development of novel plant communities without analogues in the fossil record. These communities may be poorer at sequestering carbon and may respond differently to future climate change.
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Biodiversidade , Sphagnopsida , Mudança Climática , Humanos , Plantas , SoloRESUMO
PURPOSE: Radiation therapy is often the last resource treatment for cervical relapse in iodine refractory differentiated thyroid cancer. We present locoregional control data in patients with cervical relapse treated with curative intent radiation therapy with or without concomitant carboplatin. MATERIAL AND METHODS: This monocentric retrospective study gathered data on patients with differentiated thyroid carcinoma - vesicular or papillary - in relapse after thyroidectomy who received a curative intent cervical radiation therapy. Locoregional progression free survival (LRPFS), progression free survival (PFS), overall survival (OS) were gathered as well as acute and chronic adverse events assessed with the CTCAE v4. RESULTS: Thirty-nine patients were consecutively included between 2005 and 2019. The median follow-up was 36.6months. Fifteen patients (38%) had a locoregional relapse, locoregional control at 2years was 66.7%. The median LRPFS was 48months [32.9-not reached] and the median overall survival 49months [38.8-not reached]. In multivariate analysis, initial incomplete resection was associated with poorer OS (HR: 24.39 [3.57-166.78], P=0.00113) and LRPFS (HR: 33.91 [4.46-257.61], P=0.00066), extra nodal spread was associated with poorer LRPFS (HR: 13.45 [1.81-99,76], P=0.011). ECOG performance status was associated with OS (HR: 5.11 [1.57-16.66], P=0.00688). Carboplatin association with radiation therapy was not associated with improved survivals (OS: P=0.34, LRPFS: P=0.84). The rate of acute grade 3 toxicities was 14%. CONCLUSION: Salvage cervical radiation therapy was associated with a locoregional control of 66.7% at 2years with a reasonable toxicity rate. Carboplatin association with radiation therapy did not improve locoregional control nor overall survival in comparison with radiotherapy alone.
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Adenocarcinoma , Neoplasias da Glândula Tireoide , Adenocarcinoma/patologia , Carboplatina/uso terapêutico , Quimiorradioterapia , Humanos , Recidiva Local de Neoplasia/radioterapia , Estudos Retrospectivos , Terapia de Salvação , Neoplasias da Glândula Tireoide/radioterapiaAssuntos
Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Respiração Artificial , Prognóstico , Mortalidade , ReflexoRESUMO
This paper explores the prospect of CMOS devices to assay lead in drinking water, using calorimetry. Lead occurs together with traces of radioisotopes, e.g., 210Pb, producing g-emissions with energies ranging from 10 keV to several 100 keV when they decay; this range is detectable in silicon sensors. In this paper we test a CMOS camera (OXFORD INSTRUMENTS Neo 5.5) for its general performance as a detector of X-rays and low energy g-rays and assess its sensitivity relative to the World Health Organization upper limit on lead in drinking water. Energies from 6 keV to 60 keV are examined. The CMOS camera has a linear energy response over this range and its energy resolution is for the most part slightly better than 2%. The Neo sCMOS is not sensitive to X-rays with energies below ~10 keV. The smallest detectable rate is 40 ± 3 mHz, corresponding to an incident activity on the chip of 7 ± 4 Bq. The estimation of the incident activity sensitivity from the detected activity relies on geometric acceptance and the measured efficiency vs. energy. We report the efficiency measurement, which is 0.08(2)% (0.0011(2)%) at 26.3 keV (59.5 keV). Taking calorimetric information into account we measure a minimal detectable rate of 4 ± 1 mHz (1.5 ± 0.1 mHz) for 26.3 keV (59.5 keV) g-rays, which corresponds to an incident activity of 1.0 ± 0.6 Bq (57 ± 33 Bq). Toy Monte Carlo and Geant4 simulations agree with these results. These results show this CMOS sensor is well-suited as a g- and X-ray detector with sensitivity at the few to 100 ppb level for 210Pb in a sample.
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Mechanisms of late radio-induced lesions are the result of multiple and complex phenomena, with many entangled cellular and tissue factors. The biological continuum between acute and late radio-induced effects will be described, with firstly a break in homeostasis that leads to cellular redistributions. New insights into late toxicity will finally be addressed. Individual radiosensitivity is a primary factor for the development of late toxicity, and clinicians urgently need predictive tests to offer truly personalized radiation therapy. An update will be made on the various functional and genetic tests currently being validated. The management of radio-induced side effects remains a frequent issue for radiation oncologists, and an update will be made for certain specific clinical situations. Finally, an innovative management for patients with significant side effects after pelvic radiotherapy will be developed, involved mesenchymal stem cell transplantation, with the presentation of the "PRISME" protocol currently open to patients recruitment.
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Neoplasias/radioterapia , Lesões por Radiação/terapia , Terapia Combinada , Humanos , Neoplasias/cirurgia , Lesões por Radiação/etiologia , Tolerância a Radiação , Radioterapia/efeitos adversos , Transplante de Células-Tronco , Fatores de TempoRESUMO
Intracranial radiotherapy has been improved, primarily because of the development of stereotactic approaches. While intracranial stereotactic body radiotherapy is mainly indicated for treatment of benign or malignant tumors, this procedure is also effective in the management of other neurological pathologies; it is delivered using GammaKnife® and linear accelerators. Thus, brain arteriovenous malformations in patients who are likely to experience permanent neurological sequelae can be managed by single session intracranial stereotactic body radiotherapy, or radiosurgery, in specific situations, with an advantageous benefit/risk ratio. Radiosurgery can be recommended for patients with disabling symptoms, which are poorly controlled by medication, such as trigeminal neuralgia, and tremors, whether they are essential or secondary to Parkinson's disease. This literature review aims at defining the place of intracranial stereotactic body radiotherapy in the management of patients suffering from non-tumoral refractory neurological pathologies. It is clear that the multidisciplinary collaboration of experienced teams from Neurosurgery, Neurology, Neuroradiology, Radiation Oncology and Medical Physics is needed for the procedures using high precision radiotherapy techniques, which deliver high doses to locations near functional brain areas.
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Malformações Arteriovenosas Intracranianas/radioterapia , Radiocirurgia , Neuralgia do Trigêmeo/radioterapia , HumanosRESUMO
Vegan and vegetarian diets are becoming increasingly popular. Dietary restrictions may increase the risk of iodine deficiency. This systematic review aims to assess iodine intake and status in adults following a vegan or vegetarian diet in industrialised countries. A systematic review and quality assessment were conducted in the period May 2019-April 2020 according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies were identified in Ovid MEDLINE, Embase, Web of Science, PubMed, Scopus, and secondary sources. Fifteen articles met inclusion criteria. Participants included 127,094 adults (aged ≥ 18 years). Vegan groups presented the lowest median urinary iodine concentrations, followed by vegetarians, and did not achieve optimal status. The highest iodine intakes were recorded in female vegans (1448.0 ± 3879.0 µg day-1) and the lowest in vegetarians (15.6 ± 21.0 µg day-1). Omnivores recorded the greatest intake in 83% of studies. Seaweed contributed largely to diets of vegans with excessive iodine intake. Vegans appear to have increased risk of low iodine status, deficiency and inadequate intake compared with adults following less restrictive diets. Adults following vegan and vegetarian diets living in countries with a high prevalence of deficiency may be more vulnerable. Therefore, further monitoring of iodine status in industrialised countries and research into improving the iodine intake and status of adults following vegan and vegetarian diets is required.