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1.
Evol Appl ; 17(8): e13765, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39091352

RESUMEN

Conservation and sustainable management of lineages providing non-timber forest products are imperative under the current global biodiversity loss. Most non-timber forest species, however, lack genomic studies that characterize their intraspecific variation and evolutionary history, which inform species' conservation practices. Contrary to many lineages in the Andean biodiversity hotspot that exhibit high diversification, the genus Parajubaea (Arecaceae) has only three species despite the genus' origin 22 million years ago. Two of the three palm species, P. torallyi and P. sunkha, are non-timber forest species endemic to the Andes of Bolivia and are listed as IUCN endangered. The third species, P. cocoides, is a vulnerable species with unknown wild populations. We investigated the evolutionary relationships of Parajubaea species and the genetic diversity and structure of wild Bolivian populations. Sequencing of five low-copy nuclear genes (3753 bp) challenged the hypothesis that P. cocoides is a cultigen that originated from the wild Bolivian species. We further obtained up to 15,134 de novo single-nucleotide polymorphism markers by genotyping-by-sequencing of 194 wild Parajubaea individuals. Our total DNA sequencing effort rejected the taxonomic separation of the two Bolivian species. As expected for narrow endemic species, we observed low genetic diversity, but no inbreeding signal. We found three genetic clusters shaped by geographic distance, which we use to propose three management units. Different percentages of missing genotypic data did not impact the genetic structure of populations. We use the management units to recommend in situ conservation by creating new protected areas, and ex situ conservation through seed collection.

2.
J Ethnobiol Ethnomed ; 20(1): 53, 2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38762450

RESUMEN

While ethnobiology is a discipline that focuses on the local, it has an outstanding, but not yet fully realized potential to address global issues. Part of this unrealized potential is that universalistic approaches often do not fully recognize culturally grounded perspectives and there are multiple challenges with scaling up place-based research. However, scalability is paramount to ensure that the intimate and context-specific diversity of human-environmental relationships and understandings are recognized in global-scale planning and policy development. Here, we identify four pathways to enable the scalability of place-based ethnobiological research from the ground up: local-to-global dialogues, aggregation of published data, multi-sited studies, and geospatial analyses. We also discuss some major challenges and consideration to encourage continuous reflexivity in these endeavours and to ensure that scalability does not contribute to unnecessarily decontextualizing, co-opting, or overwriting the epistemologies of Indigenous Peoples and local communities. As ethnobiology navigates multiple scales of time and space and seeks to increase its breadth, this study shows that the use of deliberately global approaches, when carefully nested within rich field-based and ecological and ethnographically grounded data, can contribute to: (1) upscaling case-specific insights to unveil global patterns and dynamics in the biocultural contexts of Indigenous Peoples and local communities; (2) bringing ethnobiological knowledge into resolutions that can influence global environmental research and policy agendas; and (3) enriching ethnobiology's field-based ethos with a deliberate global analytical focus.


Asunto(s)
Antropología Cultural , Humanos
3.
Braz J Med Biol Res ; 56: e13018, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37970925

RESUMEN

The aim of this study was to characterize the normality of the fetal circulatory system through the time between ventricular systoles of the ductus venosus in the three gestational trimesters in healthy fetuses using nonlinear methods of the complexity of the signal. A prospective cohort study was conducted at the Instituto de Medicina Integral Prof. Fernando Figueira (IMIP) from December 2019 to May 2020. Pregnant women between 11 and 14 weeks, with intrauterine pregnancy and healthy fetus were included. Patients with multiple gestation, positive screening for congenital malformation, including heart disease, and under 18 years of age were excluded. Doppler velocimetry ultrasonography of the ductus venosus was performed between the 11th and 14th weeks, 20th and 24th weeks, and 28th and 32nd weeks of gestation, and then the sound signal was extracted and segmented from the videos. To compare the means between the gestational trimesters of the approximate entropy (ApEn) and Lempel-Ziv complexity (CLZ) of the time between ventricular systoles, the Friedman test was used, with a significance level of 5%. No statistically significant difference was found between the 1st, 2nd, and 3rd trimesters regarding the mean ApEn (P=0.281) and CLZ (P=0.595) of the time between ventricular systoles of the ductus venosus. Ductus venosus systolic time was not sensitive to differentiate fetal cardiovascular dynamics between gestational trimesters. This study pioneered the characterization of cardiovascular normality by nonlinear parameters of the fetal ductus venosus in all three trimesters.


Asunto(s)
Sistema Cardiovascular , Ultrasonografía Prenatal , Embarazo , Humanos , Femenino , Adolescente , Estudios Prospectivos , Ultrasonografía , Tercer Trimestre del Embarazo , Velocidad del Flujo Sanguíneo , Feto/diagnóstico por imagen , Feto/irrigación sanguínea , Edad Gestacional
4.
Braz J Biol ; 83: e275302, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38018524

RESUMEN

In this study, we investigated the infection by pulmonary parasites in the water snake Helicops angulatus. We found four nymphs of the pentastomide parasite Sebekia oxycephala, parasitizing two adult females H. angulatus collected in the municipality of Rio Tinto, Paraíba, Brazil. This occurrence is likely due to the nymphs of this parasite directly infecting aquatic intermediate hosts, such as fish. The result of this study represents the first record of pentastomid infecting H. angulatus.


Asunto(s)
Colubridae , Pentastomida , Animales , Femenino , Colubridae/parasitología , Brasil/epidemiología , Pulmón , Ninfa
6.
Heliyon ; 9(4): e14922, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37089371

RESUMEN

Deep-renovations measures are identified as possible solutions to support European Union's natural gas phase-out and fuel independency. However, it has been difficult to increase renovation rates (about 1% per year), and previous studies have recognized socio-economic barriers as one of the reasons for that. Then, integrated (techno-socio-economic) datasets are vital to support building policy measures that circumvent the negative consequences of high gas prices. This paper's main objective is to develop and to test a methodology that merges two data sources: the European Union Statistics on Income and Living Conditions and the Household Budget Survey in order to create an integrated techno-socio-economic dataset. The following research questions are answered: What is the replicable methodology for merging both datasets in order to create an accurate statistical model? What can we learn about household savings and natural gas expenditures of household types characterised by ownership status and dwelling type? The modelling results show that the developed logistic regression model presented an accuracy of 77% using 2015 data from Spain. The explorative statistical analysis showed that the owner-occupied single-family houses predominate in the highest natural gas expenditure quintiles, while the rented single-family houses in the lowest quintiles, indicating that ownership status may have a stronger influence on the natural gas expenditure than building type. The mean annual household savings are negative, an evidence of households' budget restrictions to finance deep renovation activities. As a conclusion, the generated techno-socio-economic synthetic dataset provides useful information about the relation between household budget restrictions, natural gas expenditure and potential investment on deep renovation. Based on the generated dataset, it is also concluded that higher natural gas prices alone are not sufficient to stimulate deep renovations. For boosting renovation activities, the design of financing and incentive schemes should be end-user targeted considering the households' heterogeneity. Then, the definition of households' profiles should include ownership status and other socio-economic parameters not only dwelling type. This work prepares the ground for setting techno-socio-economic databases that can be used to design more accurate incentives and financing schemes to accelerate European building stock decarbonisation and fossil fuel independency.

7.
Clin Radiol ; 78(3): e268-e278, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36623977

RESUMEN

AIM: To evaluate bone marrow fat fraction using the Dixon technique (FFDix) of magnetic resonance imaging (MRI) as a potential biomarker of haemolysis and clinical severity in the overall assessment and follow-up of sickle cell disease (SCD) patients. MATERIAL AND METHODS: The present study was a cross-sectional study in which healthy individuals and SCD patients (matched for age, sex, and weight) were subjected to MRI of the lumbar spine and pelvis to quantify FFDix in the bone marrow using the Dixon technique. SCD severity was analysed by clinical and laboratory data, and an online calculator. A high degree of haemolysis was defined using the cut-off values haemoglobin (Hb) ≤10 g/dl, lactate dehydrogenase (LDH) ≥325 U/l, reticulocytes ≥3% and total bilirubin (TB) ≥1.2 mg/dl. Pearson's correlation, receiver operating characteristic (ROC) curve and binary logistic regression analysis were performed. RESULTS: Forty-eight SCD patients (26 homozygous: HbSS and 22 compound heterozygous: HbSC) and 48 healthy individuals participated in the study. FFDix was lower in SCD patients than in the control group, showing even lower values in the HbSS subtype and patients with a higher degree of haemolysis. HbSC patients with a higher degree of haemolysis using hydroxyurea (medium dosage 9.8 mg/kg/day) had lower FFDix. ROC curves and odds ratios for detecting patients with a higher degree of haemolysis at the different FFDix measurement sites demonstrated excellent performance: iliac bones (cut-off ≤16.75%, AUC = 0.824, p<0.001), femoral heads (cut-off ≤46.7%, AUC = 0.775, p=0.001), lumbar vertebrae (cut-off ≤7.8%, AUC = 0.755, p=0.002). CONCLUSION: Decreased FFDix is indicative of higher degree of haemolysis and SCD severity with great potential as a non-invasive biomarker contributing to the overall assessment and follow-up of SCD patients.


Asunto(s)
Anemia de Células Falciformes , Enfermedad de la Hemoglobina SC , Humanos , Hemólisis , Médula Ósea , Estudios Transversales , Anemia de Células Falciformes/complicaciones , Anemia de Células Falciformes/diagnóstico por imagen , Hemoglobina Falciforme , Biomarcadores
8.
J Econ Entomol ; 116(1): 192-201, 2023 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-36534944

RESUMEN

We assessed bioactivity of ethanolic extracts from 35 species of Jatropha L. against an ornamental plant pest, the azalea lace bug, Stephanitis pyrioides (Scott). Jatropha extracts were prepared by air-drying stem, root, or whole plant material, grinding the tissue into a fine powder, adding 70% ethanol, and then vacuum filtering the contents. Emulsions included the extract diluted to the desired concentration in de-ionized water and 10% dimethyl sulfoxide (DMSO). Treatments involved pipetting 20 µl of emulsion onto three adult lace bugs in each well of a 96-well microtiter plate. Treated wells served as replicates for each of six extract concentrations and were arranged according to a RCBD. Extracts of Jatropha clavuligera Müll. Arg. and J. ribifolia (Pohl) Ballion from 0.06 to 0.50% were the most acutely bioactive with bug mortality exceeding that of the positive control - azadirachtin, a terpenoid and chief active ingredient in neem oil. At 1.00%, extracts of J. clavuligera, J. ribifolia and azadirachtin killed 100% of bugs within 3 hr. Jatropha clavuligera induced the lowest LC50 and ranked first in insecticidal potency based on ≥98% of bugs dying within 3 hr. Extracts of J. curcas L., J. gossypiifolia L., J. excisa Griseb, and azadirachtin were equally bioactive; although after 3 hr, the three Jatropha species killed bugs faster. When compared with DMSO, all extract emulsions were bioactive against adult bugs. Thus, active ingredients in a new biopesticide could be sourced from the stem, root, or whole plant extracts of at least five Jatropha species.


Asunto(s)
Heterópteros , Insecticidas , Jatropha , Animales , Insecticidas/farmacología , Dimetilsulfóxido , Emulsiones , Extractos Vegetales/farmacología
9.
Braz. j. med. biol. res ; 56: e13018, 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1520476

RESUMEN

The aim of this study was to characterize the normality of the fetal circulatory system through the time between ventricular systoles of the ductus venosus in the three gestational trimesters in healthy fetuses using nonlinear methods of the complexity of the signal. A prospective cohort study was conducted at the Instituto de Medicina Integral Prof. Fernando Figueira (IMIP) from December 2019 to May 2020. Pregnant women between 11 and 14 weeks, with intrauterine pregnancy and healthy fetus were included. Patients with multiple gestation, positive screening for congenital malformation, including heart disease, and under 18 years of age were excluded. Doppler velocimetry ultrasonography of the ductus venosus was performed between the 11th and 14th weeks, 20th and 24th weeks, and 28th and 32nd weeks of gestation, and then the sound signal was extracted and segmented from the videos. To compare the means between the gestational trimesters of the approximate entropy (ApEn) and Lempel-Ziv complexity (CLZ) of the time between ventricular systoles, the Friedman test was used, with a significance level of 5%. No statistically significant difference was found between the 1st, 2nd, and 3rd trimesters regarding the mean ApEn (P=0.281) and CLZ (P=0.595) of the time between ventricular systoles of the ductus venosus. Ductus venosus systolic time was not sensitive to differentiate fetal cardiovascular dynamics between gestational trimesters. This study pioneered the characterization of cardiovascular normality by nonlinear parameters of the fetal ductus venosus in all three trimesters.

10.
Clin Nutr ESPEN ; 52: 138-143, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36513446

RESUMEN

BACKGROUND & AIMS: Phase angle (PhA) has been used as an indicator of nutritional status. However, the significance of PhA reduction after bariatric surgery is less known. This study evaluated PhA and its relation with biochemical parameters and prognostic inflammatory and nutritional indices at a one-year follow-up of patients subjected to Roux-en-Y bypass (RYGB) or sleeve gastrectomy (SG). METHODS: Our final sample consisted of 25 patients subjected to RYGB and 11 to SG. Body mass index, fat-free mass, fat mass, PhA, serum transthyretin (TTR), albumin, C-reactive protein, alpha-1-acid glycoprotein, and prognostic inflammatory and nutritional indices were evaluated at four time points: before and approximately two, six, and 12 months after RYGB or SG. One-way repeated measures ANOVA or the Friedman test with Tukey's post hoc test was used depending on data distribution. The correlation between PhA and biochemical parameters and indices were evaluated using Spearman's or Pearson's correlation coefficients. RESULTS: Except for serum albumin, all parameters significantly decreased over time (p < 0.001). Only the RYGB group showed transthyretinTR values below reference ones. Prognostic indices significantly decreased in both groups (p < 0.001). We found a significant positive correlation of PhA with TTR in both RYGB (r = 0.475; p < 0.001) and SG (r = 0.457; p < 0.001). CONCLUSIONS: Data suggest that at a one-year follow-up after bariatric surgery, lower PhA values might indicate a concomitant loss of visceral protein and a worsening of protein nutritional status.


Asunto(s)
Derivación Gástrica , Obesidad Mórbida , Humanos , Obesidad Mórbida/cirugía , Obesidad Mórbida/complicaciones , Estado Nutricional , Pérdida de Peso , Gastrectomía , Proteína C-Reactiva
11.
Oper Dent ; 47(4): 392-402, 2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35917238

RESUMEN

OBJECTIVE: To evaluate the physical and biological properties of different types of flowable resin composites and their bonding ability to dentin, comparing the performance of self-adhesive and bulk-fill materials with a conventional control. METHODS AND MATERIALS: Four flowable resin composites were tested: two self-adhesive (Y-flow [SA_YF]; and Dyad Flow [SA_DF]); one bulk-fill (Filtek Bulk Fill Flow [BF]); and one conventional composite (Opallis Flow [OF]). The microshear bond strength (µSBS) to dentin (bovine samples) was investigated at 24 hours and 6 months of storage. The materials were also characterized by degree of conversion, cross-link density, water contact angle, color stability, and cell viability (ISO 10993-5/2009) analyses. Data were analyzed using Analysis of Variance and Tukey tests (α=0.05). RESULTS: The µSBS values were higher for control specimens at 24 hours, whereas the resin-dentin bonds were similarly distributed among the groups after aging. Adhesive failure was the most frequent pattern observed at both time intervals. SA_YF was the only material that increased the bond strength over time. Degree of conversion increased in the following order: SA_YF (28.6±1.4%) < BF (49.7±0.8%) < OF (60.0±2.0%) = SA_DF (63.6±2.3%). Cross-link density was similar among all materials. The self-adhesive composites were more hydrophilic than the other types, with BF showing the lowest water contact angle and the greatest color alteration. All resin composites had a biocompatible behavior. CONCLUSION: Chemical composition appeared to be an influential factor affecting the physico-mechanical and biological behavior of the materials tested.


Asunto(s)
Resinas Compuestas , Cementos de Resina , Animales , Bovinos , Resinas Compuestas/química , Ensayo de Materiales , Cementos de Resina/química , Agua
12.
Oper Dent ; 47(3): 268-278, 2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-35584331

RESUMEN

This study evaluated the retention of composite resin restorations in noncarious cervical lesions (NCCLs) performed with or without pretreatment with 10% NaOCl solution (deproteinization). A randomized, controlled, split-mouth, double-blinded trial was carried out. Thirty patients with at least two NCCLs were included in the study. The NCCLs were randomly allocated into two treatment groups: control (acid etching with 37% phosphoric acid + placebo solution + Adper Single Bond 2/3M Oral Care + Filtek Z350/3M Oral Care) or experimental group (acid etching with 37% phosphoric acid + 10% NaOCl solution + Adper Single Bond 2 + Filtek Z350). A calibrated examiner evaluated the restorations at baseline (1 week) and recalls (6, 12, 24, and 36 months) using the FDI criteria. The primary outcome evaluated was retention of the restorations. Data were analyzed by the Kaplan-Meier method and the log-rank test (α=0.05). After 3 years, 64 restorations were evaluated in 23 patients. The annual failure rate was 9% for the control group and 17.8% for the experimental group (deproteinization technique). Considering the failures and their distribution among the characteristics of the patients and NCCLs, no statistically significant differences were observed for the control and experimental treatment groups (p=0.077) or the number of teeth in the mouth (p=0.320). Restorations in the mandible (p=0.039) and premolars (p=0.013) showed significantly lower clinical survival rates. The deproteinization pretreatment with a 10% NaOCl solution did not promote additional retention of restorations in NCCLs. (clinicaltrials. gov: NCT03086720).


Asunto(s)
Resinas Compuestas , Restauración Dental Permanente , Resinas Compuestas/química , Resinas Compuestas/uso terapéutico , Restauración Dental Permanente/métodos , Humanos
13.
Naunyn Schmiedebergs Arch Pharmacol ; 394(3): 437-446, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33034715

RESUMEN

Arterial hypertension is a risk factor for various cardiovascular and renal diseases, representing a major public health challenge. Although a wide range of treatment options are available for blood pressure control, many hypertensive individuals remain with uncontrolled hypertension. Thus, the search for new substances with antihypertensive potential becomes necessary. Coumarins, a group of polyphenolic compounds derived from plants, have attracted intense interest due to their diverse pharmacological properties, like potent antihypertensive activities. Braylin (6-methoxyseselin) is a coumarin identified in the Zanthoxylum tingoassuiba species, described as a phosphodiesterase-4 (PDE4) inhibitor. Although different coumarin compounds have been described as potent antihypertensive agents, the activity of braylin on the cardiovascular system has yet to be investigated. To investigate the vasorelaxation properties of braylin and its possible mechanisms of action, we performed in vitro studies using superior mesenteric arteries and the iliac arteries isolated from rats. In this study, we demonstrated, for the first time, that braylin induces potent vasorelaxation, involving distinct mechanisms from two different arteries, isolated from rats. A possible inhibition of phosphodiesterase, altering the cyclic adenosine monophosphate (cAMP)/cAMP-dependent protein kinase (PKA) pathway, may be correlated with the biological action of braylin in the mesenteric vessel, while in the iliac artery, the biological action of braylin may be correlated with increase of cyclic guanosine monophosphate (cGMP), followed by BKCa, Kir, and Kv channel activation. Together, these results provide evidence that braylin can represent a potential therapeutic use in preventing and treating cardiovascular diseases.


Asunto(s)
Cumarinas/farmacología , Arteria Ilíaca/efectos de los fármacos , Arterias Mesentéricas/efectos de los fármacos , Vasodilatadores/farmacología , Animales , Arteria Ilíaca/fisiología , Masculino , Arterias Mesentéricas/fisiología , Canales de Potasio/fisiología , Ratas Wistar , Vasodilatación/efectos de los fármacos
14.
Oper Dent ; 46(1): E21-E33, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-32926155

RESUMEN

CLINICAL RELEVANCE: The literature reviewed suggests that airborne particle abrasion has no negative effects on the bond strength of resin-based materials to dentin and that a positive influence on dentin bond strength was only achieved in specific air-abrasion conditions. SUMMARY: In this systematic review the authors investigated how airborne-particle abrasion (APA) using aluminum oxide affects the bond strength of resin-based materials to dentin. The search was performed in three databases. In vitro studies (Type of study) comparing the bond strength of resin-based materials (Outcome) to air-abraded (Intervention) compared with non-air-abraded (Comparison) human dentin (Population) were included (the PICOT elements are given parenthetically). From 5437 unique articles, 65 were read in full, 33 were included in the qualitative synthesis, and 32 were included in the meta-analysis. Methodologic quality and risk of bias were assessed. Comparisons were performed between air-abraded and control dentin groups by adopting a random-effects model (α=0.05). Additional analyses were carried out for the different parameters used in APA: type of surface treatment in the control group, particle size, air pressure, and APA duration. The bond strength to air-abraded dentin was favored only when the control surface was treated with a hand excavator. For particle size, APA was favored when the particle size was >30 µm and the controls were no treatment or hand excavator or when the particle size was ≤30 µm and the control was bur. In addition, the results favored air-abraded groups only when the pressure was > 5 bar and bur was used in the control group. No significant differences were observed for duration of APA. No comparison on bond strength considering the presence of aging conditions was possible in the included studies due to the low number of studies that aged the specimens. In conclusion, APA had no negative effects on the bond strength of resin-based materials to dentin and was able to improve the dentin bond strength only when the particle size was > 30 µm and air pressure was > 5 bar. PROSPERO registration protocol: CRD42018096128.


Asunto(s)
Recubrimiento Dental Adhesivo , Anciano , Óxido de Aluminio , Resinas Compuestas , Dentina , Humanos , Ensayo de Materiales , Cementos de Resina , Resistencia al Corte , Propiedades de Superficie
15.
Oper Dent ; 46(1): 63-74, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33351938

RESUMEN

CLINICAL RELEVANCE: The use of multipeak LED light-curing guarantees efficiency on light activation of Ivocerin-containing light-cured resin cement.


Asunto(s)
Luces de Curación Dental , Cementos de Resina , Curación por Luz de Adhesivos Dentales , Ensayo de Materiales
16.
Extr Ind Soc ; 7(4): 1347-1350, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32895631

RESUMEN

The COVID-19 pandemic exposes both conflict and cooperation in artisanal and small-scale gold mining in the Brazilian Amazon. Reporting on the experiences of artisanal and small-scale gold miners (garimpeiros, in Brazilian Portuguese), we show how, on the one hand, the pandemic challenges an already precarious working system that could lead garimpeiros, often invisible to public policies, to positions of further vulnerability; and, on the other hand, highlights the capacity of garimpeiros to self-organize and navigate the difficulties by finding alternative solutions to cope with the crisis. This leads us to argue that emerging strategies of cooperation, related to self-organization and communication channels have the potential to provide experiences useful for processes of conflict transformation in the post-crisis. We acknowledge that much depends on the severity of the crisis and its manifestations in the region; nevertheless, the potential for constructive outcomes from the crisis should not be disregarded.

17.
Clin Radiol ; 75(6): 441-447, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32061396

RESUMEN

AIM: To describe the magnetic resonance imaging (MRI) findings of the cervical spine of patients with mucopolysaccharidosis type VI (MPS VI) and correlate them with clinical manifestations. MATERIALS AND METHODS: This is a cross-sectional study involving 12 patients with MPS VI. A limited neurological examination was undertaken in each patient including Tinel's test, assessment of muscle tone, and the evaluation of deep tendon reflexes. Additionally, each patient underwent cervical spine MRI to evaluate platybasia, odontoid dysplasia, periodontoid soft-tissue thickening, spinal canal stenosis, myelopathy, basilar invagination, platyspondyly, and reduction of nasopharyngeal airway. RESULTS: Nine patients were male (75%). The average age was 12.5 (±3.5 years). Tinel's test was negative in all patients. No muscle tone abnormalities were observed. Approximately 48% of the tested reflexes were considered abnormal, 10 of which (8.3%) were pathological occurring in five different patients (41.6%). At MRI, all patients showed periodontoid soft-tissue thickening and cervical spinal stenosis; six showed spinal cord compression and two showed myelopathy. Odontoid hypoplasia and basilar invagination were observed in nine patients. All patients with cervical stenosis on MRI had abnormal reflexes; however, only two of the six patients with evidence of cord compression on MRI had abnormal reflexes on clinical examination. CONCLUSIONS: The present study of 12 patients with MPS VI demonstrated that a normal neurological examination cannot confidently exclude potential cord compression in patients with this condition. MRI may aid in the timely identification of cervical spine abnormalities, and potentially play a role in lessening morbidity and mortality in patients with MPS.


Asunto(s)
Vértebras Cervicales/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Mucopolisacaridosis VI/diagnóstico por imagen , Compresión de la Médula Espinal/diagnóstico por imagen , Niño , Estudios Transversales , Femenino , Humanos , Masculino , Examen Neurológico
20.
Oper Dent ; 44(5): 536-544, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30978159

RESUMEN

This study investigated the stability of the optical properties of high-translucent shades of dental resin-based composites. Four commercial materials (Filtek Z350 XT, Opallis, Amelogen Plus, and IPS Empress Direct) and 14 non-Vita shades were tested. Disc-shaped specimens for each resin-based composite-shade combination (n=6) were evaluated at T0 (baseline), T1 (after 30 days of storage in water), and T2 (after 30 days of storage each in water and a coffee solution). Color measurements were performed according to the L'C'h' color system. Translucency Parameter (TP) and CIEDE2000 color difference (ΔE00) were calculated. Data were statistically analyzed at α = 0.05. Baseline TP values varied from 43 ± 1 to 55 ± 1. Changes in TP at T1 varied from -3.0% (Opallis T-Neutral) to 4.2% (Amelogen Plus Trans Orange), with no major differences from T0. At T2, most resin-based composites showed significantly increased opacity, with changes varying between -15.0% (Empress Direct Trans 20) and -2.7% (Z350 XT Blue). However, the TP values were ≥40 throughout the study. Storage in water caused negligible color differences, with ΔE00 values at T1 ≤ 0.9 ± 0.6. At T2, all materials tested showed significant color difference, and ΔE00 ≥ 3.2 ± 0.2. The orange shades from Opallis and Amelogen Plus showed lower color variation than did the other shades. The most significant optical changes upon storage were detected in the hue and particularly the chroma color coordinate. In conclusion, the high-translucent resin-based composites showed large variability in the stability of their optical properties among the tested brands and different shades of the same material. Regardless of the storage condition, the tested resin-based composites retained their high-translucency character over time.


Asunto(s)
Resinas Compuestas , Materiales Dentales , Color , Colorimetría , Ensayo de Materiales
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