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1.
Sci Total Environ ; 953: 176012, 2024 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-39236817

RESUMEN

Sediment nutrients can be mobilized to overlying water via internal loading, which can be important to aquatic productivity. Using data from 143 Canadian lakes, we show high (~2400-fold) variation of soluble reactive phosphorus (SRP) concentrations in surficial sediment porewater, with results suggesting internal phosphorus loading (IPL) is also likely to vary widely. Consistent with past work at smaller scales, we show that lake depth, pH, trophic status, and bulk sediment Al:P and Fe:P influence porewater SRP, and IPL. Median porewater SRP concentration in lakes with high Al:P (molar ratios >10) were 4.8-fold smaller than in lakes with lower Al:P. In lakes where bulk sedimentary Fe:P molar ratios were >10 porewater SRP was 3.9-fold lower than in lakes with lower Fe:P. High pH (>7.8), along with hyper-eutrophic lakes were associated with higher porewater SRP. Finally, shallow lakes (<4 m depth) had median porewater SRP concentration 6-fold higher than deep lakes (>9 m depth). Important regional differences emerged, linked to regional variation in pH, soils, lake depth and trophic status, and paralleling areas of poor water quality. For example, median porewater SRP in lakes from the Boreal Plains and Prairies ecozones (dominated by Chernozems/Mollisols) was 64-fold and 44-fold higher than in the Boreal Shield (dominated by Podzols/Spodosols) (respectively), although we note that IPL risk is likely important across many ecozones. Using national data, we found in-lake measurements (particularly pH, and salinity) showed strong capacity in predicting porewater SRP (explaining 60-72 % of the variance in the data). Importantly, watershed predictors showed good predictive power, explaining ~50 % of variance in porewater SRP using variables including soil types, and % agriculture. Porewater SRP can be predicted with reasonable accuracy using easily measured variables, as can estimates of internal phosphorus loading, suggesting that landscape limnology holds strong potential in helping to inform lake management by informing understanding of in-lake nutrient sources.

2.
J Anat ; 244(4): 557-593, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38037880

RESUMEN

Piatnitzkysauridae were Jurassic theropods that represented the earliest diverging branch of Megalosauroidea, being one of the earliest lineages to have evolved moderate body size. This clade's typical body size and some unusual anatomical features raise questions about locomotor function and specializations to aid in body support; and other palaeobiological issues. Biomechanical models and simulations can illuminate how extinct animals may have moved, but require anatomical data as inputs. With a phylogenetic context, osteological evidence, and neontological data on anatomy, it is possible to infer the musculature of extinct taxa. Here, we reconstructed the hindlimb musculature of Piatnitzkysauridae (Condorraptor, Marshosaurus, and Piatnitzkysaurus). We chose this clade for future usage in biomechanics, for comparisons with myological reconstructions of other theropods, and for the resulting evolutionary implications of our reconstructions; differential preservation affects these inferences, so we discuss these issues as well. We considered 32 muscles in total: for Piatnitzkysaurus, the attachments of 29 muscles could be inferred based on the osteological correlates; meanwhile, in Condorraptor and Marshosaurus, we respectively inferred 21 and 12 muscles. We found great anatomical similarity within Piatnitzkysauridae, but differences such as the origin of M. ambiens and size of M. caudofemoralis brevis are present. Similarities were evident with Aves, such as the division of the M. iliofemoralis externus and M. iliotrochantericus caudalis and a broad depression for the M. gastrocnemius pars medialis origin on the cnemial crest. Nevertheless, we infer plesiomorphic features such as the origins of M. puboischiofemoralis internus 1 around the "cuppedicus" fossa and M. ischiotrochantericus medially on the ischium. As the first attempt to reconstruct muscles in early tetanurans, our study allows a more complete understanding of myological evolution in theropod pelvic appendages.


Asunto(s)
Evolución Biológica , Dinosaurios , Animales , Filogenia , Extremidad Inferior , Miembro Posterior/anatomía & histología , Dinosaurios/anatomía & histología , Músculo Esquelético/anatomía & histología
3.
R Soc Open Sci ; 10(8): 230481, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37593714

RESUMEN

During the Mesozoic, non-avian theropods represented one of the most successful clades globally distributed, with a wide diversity of forms. An example is the clade Megalosauroidea, which included medium- to large-bodied forms. Here, we analyse the macroevolution of the locomotor system in early Theropoda, emphasizing the Megalosauroidea. We scored the Spinosaurus neotype in a published taxon-character matrix and described the associated modifications in character states, mapping them onto a phylogeny and using these to study disparity. In the evolution of Megalosauroidea, there was the mosaic emergence of a low swollen ridge; enlargement of the posterior brevis fossa and emergence of a posterodorsal process on the ilium in some megalosauroids; emergence of a femoral head oriented anteromedially and medially angled, and appearance of posterolaterally oriented medial femoral condyles in spinosaurids. The greatest morphological disparity is in the ilium of megalosaurids; the ischium seems to have a high degree of homoplasy; there is a clear distinction in the femoral morphospace regarding megalosauroids and other theropods; piatnitzkysaurids show considerable disparity of zeugopodial characters. These reconstructions of osteological evolution form a stronger basis on which other studies could build, such as mapping of pelvic/appendicular musculature and/or correlating skeletal traits with changes in locomotor function.

4.
Environ Res ; 236(Pt 1): 116654, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37487921

RESUMEN

Phosphorus (P) in lake sediments is stored within diverse forms, often associated with metals, minerals, and organic matter. Sediment P can be remobilized to the water column, but the environmental conditions influencing the P retention-release balance depend upon the sediment chemistry and forms of P present. Sequential fractionation approaches can be used to help understand forms of P present in the sediments, and their vulnerability to release. We assessed P composition in surficial sediments (as an assemblage of six P-fractions) and its relationship with watershed, and lake-specific explanatory variables from 236 lakes across Canada. Sediment P composition varied widely across the 12 sampled Canadian ecozones. The dominant P-fractions were the residual-P and the labile organic P, while the loosely bound P corresponded to the smallest proportion of sediment TP. Notable contrasts in sediment P composition were apparent across select regions - with the most significant differences between sediment P in lakes from the mid-West Canada region (Prairies and Boreal Plains ecozones) and both Eastern coastal (Atlantic Maritime and Atlantic Highlands) and Western coastal (Pacific Maritime) ecozones. The ecozone attributes most critical to sediment P speciation across Canadian lakes were related to soil types in the watershed (e.g., podzols, chernozems, and Luvisols) and the chemical composition of lake water and sediments, such as dissolved Ca in lake water, bulk sedimentary Ca, Al, and Fe, dissolved SO4 in lake water, lake pH, and salinity. Understanding predictors of the forms of P stored in surficial sediments helps advance our knowledge of in-lake P retention and remobilization processes across the millions of unstudied lakes and can help our understanding of controls on internal P loading.

5.
Zootaxa ; 5264(4): 526-544, 2023 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-37518033

RESUMEN

We report the first occurrence in South America of spinosaurid specimens belonging to the clade Baryonychinae. The material comprises three tooth crowns recovered from the Lower Cretaceous (Berriasian-Valanginian) of the Feliz Deserto Formation, State of Sergipe, northeast Brazil. The three specimens have the typical conidont condition, displaying a fluted morphology, veined enamel texture and carinae extending to the cervix region, conditions similar to those shared among spinosaurid theropods. Furthermore, a notable feature is the presence of a serrated carinae composed of 6-7 diminutive denticles per millimetre, a key feature shared by baryonychine spinosaurids. Phylogenetic and multivariate analyses performed on dentition-based and crown-based datasets of theropod taxa confirm the relationship of the three tooth crowns described here with the well-supported spinosaurid clade. Our results retrieve the taxa which comprise the "classically" baryonychine clade as individual branches within a polytomy which includes the three tooth crowns and a subclade of spinosaurines (Spinosaurus + Angaturama/Irritator). Additionally, the discriminant and cluster analyses suggest that the materials are more similar to Suchomimus than to Baryonyx morphometrically, but clearly bearing similarities with baryonychines (sharing a similar morphospace). These new findings paleogeographically expand the occurrence of this clade to western Gondwana, and comprise one of the oldest spinosaurid records worldwide, which brings implications on hypotheses for the emergence and evolution of the clade. Furthermore, these new records indicate the presence of more than one spinosaurid taxon in the Lower Cretaceous deltaic paleoenvironment of the Feliz Deserto Formation.


Asunto(s)
Dinosaurios , Fósiles , Corona del Diente , Animales , Dinosaurios/anatomía & histología , Dinosaurios/clasificación , Filogenia , Corona del Diente/anatomía & histología , Brasil
6.
J Voice ; 2022 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-36460538

RESUMEN

OBJECTIVES: Menopause has been reported to affect the voice of female professional voice users (FPVUs). The present study aims at the development and validation of a scale to measure self-perceived menopausal voice-related limitation to work in FPVUs, henceforth the Menopausal Voice-Related Work Limitation Scale (MenoVWL). METHODS: Items were drawn from previous studies on impacts of sex steroid hormones on voice, available validated scales, and in-depth interviews with post-menopausal FPVUs. A preliminary version with 16 items was evaluated by a panel of 15 voice experts. The resulting revised version was filled in online, together with questions on current endocrinological reproductive status and related symptoms, history of amenorrhea, professional occupation, and demographic information. Responses concerning only professional voice users were selected and inclusive and exclusive criteria were applied for correct allocation of participants into pre- and post-menopausal stages within a restrict age range;192 responses were subject to factorial analysis for MenoVWL validation. Cronbach's alpha measured internal reliability. The scale was tested by comparing MenoVWL scores between pre- and post-menopausal FPVUs (98 and 94, respectively). RESULTS: Thirteen items were retained from the expert panel evaluation. Items presented a high Content Validity Index (.94 out of 1) and high Item Acceptance Ratio (86.25 %). Both exploratory and confirmatory factorial analysis rendered one dimension scale with an excellent internal consistency (Cronbach's alpha = .9). The results of a Mann-Whitney test showed a higher MenoVWL score for post- as compared to pre-menopausal FPVUs (Z = - 2.818; P = .005). CONCLUSIONS: MenoVWL is a comprehensive and validated scale with a known factor structure. It constitutes a health care and safety outcome self-perceived measure of value to the early detection of voice-related limitations to work in FPVUs during menopause.

7.
Int J Mol Sci ; 23(18)2022 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-36142396

RESUMEN

BACKGROUND: Obesity is one of the main health problems in the world today, and dysbiosis seems to be one of the factors involved. The aim of this study was to examine the impact of synbiotic supplementation on obesity and the microbiota in ob/ob mice. Twenty animals were divided into four groups: obese treated (OT), obese control (OC), lean treated (LT) and lean control (LC). All animals received a standard diet for 8 weeks. The treated groups received a synbiotic (Simbioflora-Invictus Farmanutrição Ltd., Sao Paulo, Brazil) in water, while the nontreated groups received only water. After 8 weeks, all animals were sacrificed, and gut tissue and stool samples were collected for mRNA isolation and microbiota analysis, respectively. ß-Catenin, occludin, cadherin and zonulin in the gut tissue were analyzed via RT-qPCR. Microbiome DNA was extracted from stool samples and sequenced using an Ion PGM Torrent platform. RESULTS: Synbiotic supplementation reduced body weight gain in the OT group compared with the OC group (p = 0.0398) and was associated with an increase in Enterobacteriaceae (p = 0.005) and a decrease in Cyanobacteria (p = 0.047), Clostridiaceae (p = 0.026), Turicibacterales (p = 0.005) and Coprococcus (p = 0.047). On the other hand, a significant reduction in Sutterella (p = 0.009) and Turicibacter (p = 0.005) bacteria was observed in the LT group compared to the LC group. Alpha and beta diversities were different among all treated groups. ß-Catenin gene expression was significantly decreased in the gut tissue of the OT group (p ≤ 0.0001) compared to the other groups. No changes were observed in occludin, cadherin or zonulin gene expression in the gut tissue. CONCLUSIONS: Synbiotic supplementation prevents excessive weight gain, modulates the gut microbiota, and reduces ß-catenin expression in ob/ob mice.


Asunto(s)
Microbioma Gastrointestinal , Simbióticos , Animales , Brasil , Cadherinas , Microbioma Gastrointestinal/fisiología , Ratones , Obesidad/metabolismo , Ocludina , ARN Mensajero/genética , Agua , Aumento de Peso , beta Catenina/genética
8.
J. pediatr. (Rio J.) ; 98(3): 256-263, May-June 2022. tab
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1386089

RESUMEN

Abstract Objective: To evaluate the complementary feeding practices, food intake, and nutritional status of infants on a cow's milk protein elimination diet. Methods: A cross-sectional and observational study was conducted to compare infants aged 4-18 months who were on a cow's milk protein elimination diet with a control group of healthy infants without any dietary restrictions. General information on the child's health, demographic data, and food consumption were collected. Results: The study included 96 infants in the elimination diet group and 99 in the control group. In the elimination diet group, the median age (in months) of introduction of solid foods (5.0 × 4.0; p < 0.001) and water (5.5 × 4.0; p < 0.05) was later, consumption of soft drinks and industrialized cookies was less frequent (p < 0.05), and a lower index of complementary feeding inadequacies (2.75 × 3.50; p < 0.001) was observed. The elimination diet group presented lower individual values of Z scores for weight/age, weight/height, and body mass index/age, although they were fed with higher amounts of energy (117.4 × 81.3 kcal/kg of weight; p < 0.001) and macro-and micronutrients, except for vitamin A. In the elimination diet group, breast milk and its substitutes contributed to more than 67% of energy intake. Although calcium consumption was a deficit in 31.5% of the infants, none received supplementation. Conclusion: Infants on an elimination diet presented more adequate complementary feeding practices and higher nutritional intake, despite lower body weight values.

9.
J Orthop Traumatol ; 23(1): 5, 2022 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-34997890

RESUMEN

BACKGROUND: Large Hill-Sachs lesions are considered a risk factor for recurrence of instability after arthroscopic Bankart repair alone. The aim of this study was to demonstrate that remplissage is a safe procedure that effectively reduces the risk of recurrent dislocations without causing fatty degeneration of the infraspinatus at medium-term follow-up. METHODS: Patients who underwent arthroscopic Bankart repair and remplissage with a minimum 3 years of follow-up were included. Constant-Murley (CMS), American Shoulder and Elbow Surgeons (ASES), and Walch-Duplay scores were evaluated. Magnetic resonance imaging (MRI) was performed to detect the appearance of fatty infiltration inside the infraspinatus muscle, the percentage of the Hill-Sachs lesion filled by the tendon and its integration, and the onset of rotator cuff tears. RESULTS: Thirteen patients (14 shoulders) with a mean follow-up of 55.93 (± 18.16) months were enrolled. The Walch-Duplay score was 95.00 [87.25-100.00], with a return to sport rate of 100%. Both the CMS and the ASES indicated excellent results. The affected shoulders showed a statistically significant reduction in active external rotation both with the arm at the side (ER1) and with the arm at 90° of abduction (ER2) (p = 0.0005 and p = 0.0010, respectively). A reduction in infraspinatus isometric strength was found for both ER1 and ER2, but this reduction was only statistically relevant in ER2 (p = 0.0342). There was a traumatic recurrence of instability in two cases (14.28%). MRI evaluation demonstrated an absence of adipose infiltration in 50% of cases and only a minimal amount in the remaining 50%. In 12 cases (85.72%), the capsulotenodesis completely filled the lesion and good tendon-bone integration was observed. CONCLUSION: Arthroscopic remplissage provided successful clinical outcomes without fatty infiltration of the infraspinatus and with good healing of the tissues. The low risk of recurrence was associated with an objective limitation on active external rotation, but this did not influence the patients' daily or sports activities. LEVEL OF EVIDENCE: Cohort study, level of evidence 3.


Asunto(s)
Inestabilidad de la Articulación , Luxación del Hombro , Articulación del Hombro , Artroscopía , Estudios de Cohortes , Estudios de Seguimiento , Humanos , Inestabilidad de la Articulación/diagnóstico por imagen , Inestabilidad de la Articulación/cirugía , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Recurrencia , Estudios Retrospectivos , Luxación del Hombro/diagnóstico por imagen , Luxación del Hombro/cirugía , Articulación del Hombro/diagnóstico por imagen , Articulación del Hombro/cirugía
10.
J Pediatr (Rio J) ; 98(3): 256-263, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34303657

RESUMEN

OBJECTIVE: To evaluate the complementary feeding practices, food intake, and nutritional status of infants on a cow's milk protein elimination diet. METHODS: A cross-sectional and observational study was conducted to compare infants aged 4-18 months who were on a cow's milk protein elimination diet with a control group of healthy infants without any dietary restrictions. General information on the child's health, demographic data, and food consumption were collected. RESULTS: The study included 96 infants in the elimination diet group and 99 in the control group. In the elimination diet group, the median age (in months) of introduction of solid foods (5.0 × 4.0; p < 0.001) and water (5.5 × 4.0; p < 0.05) was later, consumption of soft drinks and industrialized cookies was less frequent (p < 0.05), and a lower index of complementary feeding inadequacies (2.75 × 3.50; p < 0.001) was observed. The elimination diet group presented lower individual values of Z scores for weight/age, weight/height, and body mass index/age, although they were fed with higher amounts of energy (117.4 × 81.3 kcal/kg of weight; p < 0.001) and macro-and micronutrients, except for vitamin A. In the elimination diet group, breast milk and its substitutes contributed to more than 67% of energy intake. Although calcium consumption was a deficit in 31.5% of the infants, none received supplementation. CONCLUSION: Infants on an elimination diet presented more adequate complementary feeding practices and higher nutritional intake, despite lower body weight values.


Asunto(s)
Hipersensibilidad a la Leche , Estado Nutricional , Animales , Lactancia Materna , Bovinos , Estudios Transversales , Ingestión de Alimentos , Ingestión de Energía , Femenino , Humanos , Lactante , Fenómenos Fisiológicos Nutricionales del Lactante , Proteínas de la Leche , Leche Humana
11.
J Orthop Traumatol ; 22(1): 42, 2021 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-34698958

RESUMEN

BACKGROUND: Calcific tendinitis of the shoulder has a tendon involvement that could evolve to rotator cuff tear and shoulder osteoarthritis. This study aimed to evaluate the prevalence of glenohumeral osteoarthritis and rotator cuff tears in patients affected by calcific tendinitis at a minimum follow-up of 10 years after diagnosis. METHODS: Patients diagnosed with calcific tendinitis of the shoulder with a minimum follow-up of 10 years were contacted and invited for a clinical and radiological evaluation. Information on the demographics, affected and dominant side, bilateral shoulder pain, type of treatment, habits, systemic or musculoskeletal diseases, reoperation of the index shoulder, and subjective satisfaction was collected. The clinical evaluation was performed using Constant-Murley score (CMS), American Shoulder and Elbow Surgeons Score (ASES), and numerical rating scale (NRS); isometric strength in forwarding flexion and abduction was also measured. Each patient also underwent an ultrasound examination to evaluate rotator cuff tendon integrity and a shoulder radiograph to evaluate osteoarthritis. RESULTS: Seventy-nine patients were available for a phone interview, and 35 agreed to be examined. The mean age was 58.89 (± 7.9) years at follow-up. The prevalence of glenohumeral osteoarthritis was 17.14% in the study population, with significant progression in 14.29% of the cases, without rotator cuff full-thickness tears. x-Ray examination showed residual calcifications in 31 patients, with a mean diameter of 5.54 mm. In 30 cases, there was a reduction of the diameter; in 4 cases, the calcification increased in size; and in 1 case, the size did not change. The mean ASES score was 74.1 (± 22.7) in the group with calcifications larger than 2 mm and 89.4 (± 8.2) in patients with smaller calcifications (p = 0.08) without correlation with the type of treatment performed. CONCLUSIONS: Calcific tendinitis is a self-resolving disease without rotator cuff tears at long-term follow-up or degenerative glenohumeral progression. LEVEL OF EVIDENCE: 3, cohort study.


Asunto(s)
Lesiones del Manguito de los Rotadores , Tendinopatía , Artroscopía , Estudios de Cohortes , Humanos , Persona de Mediana Edad , Manguito de los Rotadores/diagnóstico por imagen , Lesiones del Manguito de los Rotadores/diagnóstico por imagen , Tendinopatía/diagnóstico por imagen , Tendinopatía/epidemiología , Resultado del Tratamiento
12.
An Acad Bras Cienc ; 93(suppl 2): e20201642, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34378649

RESUMEN

The Solimões and Acre basins are complex geological units related to the Andean uplift, covering the Northwestern region of Brazil, being one of the most important units due to their fossil diversity. In order to produce a document that integrates part of the fossil records of this region, we compiled/georeferenced localities from literature on which tetrapods are described, focusing on Solimões Formation but not restricted to this unit. We were able to recognize 208 localities, documented in over two centuries of reports of fossils from several taxonomic groups from the proto-Amazonia, 199 new entries in Paleobiology Database. We summarize, for each locality, its geographical position, geological information, age, and data of the paleodiversity. Most outcrops in the Amazonia region are located on river banks (~96%), while road cuts and other non-riverside outcrops represent the remainder (~4%). Most tetrapod are Mammalia, followed by Testudinata, and Crocodyliformes. This work reinforces the need for a more controlled and refined prospecting at the Solimões/Acre Basins, especially in the Solimões Formation, which represents the majority of fossiliferous records, to help answer old questions, such as dating, and new ones, here discussed, such as the paleodiversity patterns and temporal distribution among the mapped localities.


Asunto(s)
Fósiles , Mapeo Geográfico , Animales , Brasil , Reptiles , Ríos
13.
PLoS One ; 16(2): e0246839, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33556125

RESUMEN

BACKGROUND: Exclusive breastfeeding promotes beneficial modifications on the microbiota of cesarean born infants, but little is known about the role of specific breast milk components in this modulation. Women with an active FUT2 gene (called secretors) secrete α1-2 fucosylated human milk oligosaccharides (HMOs), which promote Bifidobacterium in the infant's gut and may modulate the microbiota of cesarean born infants. OBJECTIVE: To compare the microbiota composition of cesarean and vaginally born infants breastfed by secretor mothers. METHODS: Maternal secretor status was determined by the occurrence of 4 different α1-2 fucosylated HMOs in breast milk by LC-MS. The fecal microbiota composition from cesarean and vaginally born infants was analyzed by 16S rRNA gene sequencing and qPCR, stratified by the maternal secretor status, and compared. RESULTS: Alpha and beta diversity were not significantly different in cesarean born, secretor-fed infants (CSe+) compared to vaginally born, secretor-fed infants (VSe+). There were no significant differences in the fecal relative abundance of Bifidobacterium between CSe+ and VSe+ infants, but the prevalence of the species B. longum was lower in CSe+. The fecal relative abundance of Bacteroides was also lower, while Akkermansia and Kluyvera were higher in CSe+ infants. CONCLUSION: Cesarean and vaginally born infants fed with breast milk containing the α1-2 fucosylated HMOs fraction present similar amounts of Bifidobacterium in the feces, but differences are observed in other members of the microbiota.


Asunto(s)
Bacterias/clasificación , Lactancia Materna , Cesárea , Microbioma Gastrointestinal , Leche Humana/metabolismo , Madres , Oligosacáridos/metabolismo , Parto , Adulto , Bacterias/crecimiento & desarrollo , Femenino , Humanos , Lactante , Recién Nacido , Masculino
14.
Sci Rep ; 10(1): 4739, 2020 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-32179790

RESUMEN

The melting of glaciers and ice sheets is nowadays considered a symbol of climate change. Many complex mechanisms are involved in the melting of ice, and, among these processes, surface darkening due to organic material on bare ice has recently received attention from the scientific community. The presence of microbes on glaciers has been shown to decrease the albedo of ice and promote melting. Despite several studies from the Himalaya, Greenland, Andes, and Alaska, no quantitative studies have yet been conducted in the European Alps. In this paper, we made use of DNA sequencing, microscopy and field spectroscopy to describe the nature of glacier algae found at a glacier (Vadret da Morteratsch) of the European Alps and to evaluate their effect on the ice-albedo feedback. Among different algal species identified in the samples, we found a remarkable abundance of Ancylonema nordenskioeldii, a species that has never previously been quantitatively documented in the Alps and that dominates algal blooms on the Greenland Ice Sheet. Our results show that, at the end of the ablation season, the concentration of Ancylonema nordenskioeldii on the glacier surface is higher than that of other algal species (i.e. Mesotaenium berggrenii). Using field spectroscopy data, we identified a significant correlation between a reflectance ratio (750 nm/650 nm) and the algae concentration. This reflectance ratio could be useful for future mapping of glacier algae from remote sensing data exploiting band 6 (740 nm) and band 4 (665 nm) of the MultiSpectral Instrument (MSI) on board Sentinel-2 satellite. Here we show that the biological darkening of glaciers (i.e. the bioalbedo feedback) is also occurring in the European Alps, and thus it is a global process that must be taken into account when considering the positive feedback mechanisms related to glacier melting.

15.
Clinics (Sao Paulo) ; 74: e903, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31576922

RESUMEN

OBJECTIVES: To evaluate the prevalence of voluntary dehydration based on urine osmolarity in elementary school students from two public educational institutions in the metropolitan region of São Paulo and evaluate whether there is a relationship between voluntary dehydration and nutritional status or socioeconomic status. METHODS: Analytical cross-sectional study with students from two public schools in the city of Osasco. The determination of urine osmolarity was performed using the freezing method of the Advanced® Osmometer Model 3W2. Urine osmolarity greater than 800 mOsm/kg H2O was considered voluntary dehydration. During data collection, the weights and heights of the students, environmental temperatures and air humidity levels were obtained. RESULTS: A total of 475 students aged six to 12 years were evaluated, of whom 188 were male. Voluntary dehydration occurred in 63.2% of the students and was more frequent in males than in females. The prevalence of voluntary dehydration was more frequent in males aged six to nine years than in females. However, no statistically significant difference was observed between males and females aged 10 to 12 years. No association was found between voluntary dehydration and nutritional status or socioeconomic status. CONCLUSION: The prevalence of voluntary dehydration was high in elementary school students and was more frequent in males. No association was found between voluntary dehydration and nutritional or socioeconomic status.


Asunto(s)
Deshidratación/epidemiología , Concentración Osmolar , Estudiantes/estadística & datos numéricos , Orina/química , Brasil/epidemiología , Niño , Estudios Transversales , Deshidratación/fisiopatología , Femenino , Humanos , Humedad , Masculino , Estado Nutricional , Prevalencia , Factores Socioeconómicos , Temperatura , Orina/fisiología
16.
Food Chem ; 274: 691-697, 2019 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-30372996

RESUMEN

Human milk oligosaccharides (HMOs) are free glycans naturally present in human milk that act as prebiotics, prevent pathogen binding, modulate the immune system and support brain development in infants. The HMOs composition and concentrations vary significantly among different women mainly because of the direct influence of the Secretor and Lewis phenotypes on HMOs biosynthesis. Analytical methods that can identify the differences in the HMOs composition and concentrations are a fundamental tool in HMOs research. This paper describes a simple HMOs extraction and analysis for the simultaneous and absolute quantification of neutral and acidic HMOs by graphitized carbon liquid chromatography-electrospray ionization-mass spectrometry. This method was validated and applied to analyze HMOs in the human milk obtained from 10 women. This method allows accurate and reliable quantification of HMOs and can be used to determine differences in HMOs concentrations throughout lactation and among women with different Secretor and Lewis phenotypes.


Asunto(s)
Grafito/química , Leche Humana/química , Oligosacáridos/análisis , Cromatografía Líquida de Alta Presión , Femenino , Humanos , Límite de Detección , Espectrometría de Masa por Ionización de Electrospray , Estudios de Validación como Asunto
17.
Clinics ; 74: e903, 2019. tab
Artículo en Inglés | LILACS | ID: biblio-1039564

RESUMEN

OBJECTIVES: To evaluate the prevalence of voluntary dehydration based on urine osmolarity in elementary school students from two public educational institutions in the metropolitan region of São Paulo and evaluate whether there is a relationship between voluntary dehydration and nutritional status or socioeconomic status. METHODS: Analytical cross-sectional study with students from two public schools in the city of Osasco. The determination of urine osmolarity was performed using the freezing method of the Advanced® Osmometer Model 3W2. Urine osmolarity greater than 800 mOsm/kg H2O was considered voluntary dehydration. During data collection, the weights and heights of the students, environmental temperatures and air humidity levels were obtained. RESULTS: A total of 475 students aged six to 12 years were evaluated, of whom 188 were male. Voluntary dehydration occurred in 63.2% of the students and was more frequent in males than in females. The prevalence of voluntary dehydration was more frequent in males aged six to nine years than in females. However, no statistically significant difference was observed between males and females aged 10 to 12 years. No association was found between voluntary dehydration and nutritional status or socioeconomic status. CONCLUSION: The prevalence of voluntary dehydration was high in elementary school students and was more frequent in males. No association was found between voluntary dehydration and nutritional or socioeconomic status.


Asunto(s)
Humanos , Masculino , Femenino , Niño , Concentración Osmolar , Estudiantes/estadística & datos numéricos , Orina/química , Deshidratación/epidemiología , Factores Socioeconómicos , Temperatura , Orina/fisiología , Brasil/epidemiología , Estado Nutricional , Prevalencia , Estudios Transversales , Deshidratación/fisiopatología , Humedad
18.
J Cell Biochem ; 118(6): 1442-1452, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-27883213

RESUMEN

Alzheimer's disease is the most common neurodegenerative disorder. One of the factors that promotes neurodegeneration is the accumulation of senile plaques formed by Aß peptide. In this paper, it was analyzed that if oxidative stress is cause or consequence of amyloid cascade and the role of antioxidant defense system in this process, using S. cerevisiae (with a multicopy plasmid containing the Aß1-42 sequence) as experimental model. Cells grown on glycerol were more tolerant than when grown on glucose, strengthening the role of the antioxidant defense system against Aß accumulation. Antioxidant defense deficiency did not change the pattern of amyloid aggregation. On the other hand, the presence of Aß increased the level of intracellular oxidation and induced the activity of catalase, superoxide dismutase, and aconitase. Peroxissomal catalase deficient cells (Δcta1), were more sensitive to Aß toxicity than the wild type strain, while mitochondrial superoxide dismutase (Sod2) deficient cells displayed the highest frequency of petites. Besides, Aß alters the oxygen consumption and the activity of complex III and IV. Taken together, our results point out that the Aß toxicity mechanism involves an oxidative stress induction by increasing ROS production into the mitochondria, where Cta1 and Sod2 play a crucial role in the regulation of the redox balance. J. Cell. Biochem. 118: 1442-1452, 2017. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/crecimiento & desarrollo , Aconitato Hidratasa/metabolismo , Enfermedad de Alzheimer/genética , Péptidos beta-Amiloides/toxicidad , Catalasa/metabolismo , Glicerol/farmacología , Humanos , Mitocondrias/metabolismo , Modelos Biológicos , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/genética , Superóxido Dismutasa/metabolismo
19.
J Nat Prod ; 79(10): 2530-2537, 2016 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-27723329

RESUMEN

The first natural occurrence in optically active form of the dimeric flavonoid agathisflavone and definition of its axial chirality using chiroptical spectroscopic methods are described. The experimental electronic circular dichroism, electronic dissymmetry factor, optical rotatory dispersion, vibrational circular dichroism (VCD), and vibrational dissymmetry factor spectra of agathisflavone are presented and analyzed with their corresponding quantum chemical predictions to definitively assign the axial chirality of (-)-agathisflavone as (aS).


Asunto(s)
Biflavonoides/química , Dicroismo Circular , Conformación Molecular , Estructura Molecular , Dispersión Óptica Rotatoria , Estereoisomerismo
20.
JBRA Assist Reprod ; 20(2): 82-8, 2016 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-27244767

RESUMEN

The aim of this study as to analyze published evidence regarding the effectiveness of aromatase inhibitor therapy on improving spermatogenesis in infertile men. We carried out a systematic review of randomized controlled trials. The date of the most recent search was October 4, 2015. Two authors independently selected relevant clinical trials, assessing their methodological quality and extracting data. Three studies were included in this review with a total of 100 participants; however, we were able to include data from only 54 participants in the analysis. In the representation of meta-analysis with a single study comparing testolactone versus placebo, related to the hormone concentrations, there was a statistically significance difference favoring the use of testolactone for Luteinizing Hormone (LH); Estrogen (E2); free Testosterone (free T); free Estrogen (free E2); 17-Hydroxyprogesterone (17OHP); prolactin (PRL). In another analysis from a single study comparing letrozole versus anastrozole, there was also a statistically significance difference favoring the use of letrozole for the increase in both the sperm count and LH. There is only low quality evidence regarding the effectiveness of aromatase inhibitor therapy in infertile men. Further trials are needed with standardized interventions and outcomes.


Asunto(s)
Inhibidores de la Aromatasa/uso terapéutico , Azoospermia/tratamiento farmacológico , Oligospermia/tratamiento farmacológico , Humanos , Masculino , Ensayos Clínicos Controlados Aleatorios como Asunto
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