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Classifying athletes based on estimates of biological maturation (i.e., bio-banding) as a supplement to traditional age grouping has been shown to be a potential tool for enriching player development in team sports; however, bio-banding has not yet been evaluated in ice hockey. The primary aim was to investigate player experiences and coaches' selection preferences in bio-banding versus age-banding in a group of 12-13-year-old (early growth spurt) male elite players (n = 69). We also examined the relationship between somatic maturity, expressed as a % predicted adult height (%PAH), and fitness performance. Bio-banding was assessed using a questionnaire and 29 coaches selected their top players in each game based on age or bio-bands. %PAH correlated with grip strength (r = .57, p>0.001) and jumping power (r = .63, p<0.001), but not with vertical jump height, sprint time or endurance. Players who played against more mature players in bio-bands than in age groups experienced higher demands, while players who played against less mature players were able to utilize their skills to a greater extent. Coaches generally favored later-than-average maturing players who performed better on performance tests and chronologically older players in bio-banding. We conclude that bio-banding in youth ice hockey has some promising effects and warrants further evaluation.
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Desempenho Atlético , Hóquei , Humanos , Hóquei/fisiologia , Masculino , Adolescente , Projetos Piloto , Desempenho Atlético/fisiologia , Criança , Atletas , Inquéritos e Questionários , PercepçãoRESUMO
PURPOSE: Altitude training is a common strategy used with the intent to increase hemoglobin mass (Hbmass) in athletes. However, if the Hbmass is increased during altitude camps it seems to decline rapidly upon returning to sea level. This study aimed to examine the efficacy of three weekly heat training sessions over a 3.5-week period following a 3-week altitude camp, on the maintenance of Hbmass in elite cyclists. METHODS: Eighteen male cyclists (maximal oxygen consumption: 76 ± 5 mL·min-1·kg-1) underwent a 3-week altitude training camp at ~2100 m above sea level. After the camp, participants were divided into one group performing three weekly heat sessions that was subtracted from their usual training (HEAT) while the other continuing usual training (CON). Training characteristics were recorded during the intervention, while hematological measurements were recorded before the camp as well as two days and 3.5-weeks after the altitude camp. RESULTS: The 3-week altitude camp led to an overall increase in total Hbmass of 4.1%. Afterwards, HEAT maintained Hbmass (0.2%, p = 0.738), while CON group experienced a significant reduction (-3.3%, p < 0.001) (ΔHEAT vs. ΔCON, p < 0.001). Moreover, HEAT increased plasma volume (PV) by 11.6% (p = 0.007) and blood volume (BV) by 5.8% (p = 0.007), whereas CON only showed an increase in PV (5.5%, p = 0.041). Exercise intensity and training load were not different between groups during the maintenance period. CONCLUSIONS: This study suggests that incorporating three weekly heat training sessions into the usual training routine preserves a moderately increased Hbmass in elite cyclists following an altitude camp.
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In 2015, > 460,000 L of aqueous film-forming foam (AFFF) and fire suppressors containing per- and polyfluoroalkyl substances (PFAS) were used to combat a fire at a petrochemical fuel storage terminal in the Port of Santos (Brazil). Sediments from seven sites were sampled repeatedly from 2 weeks to 1 year after the fire (n = 30). Æ©15PFAS concentrations ranged from 115 to 15,931 pg g-1 dry weight (dw). Perfluorooctane sulfonic acid (PFOS) was the most frequently detected compound with concentrations ranging from 363 to 4517 (average = 1603) pg g-1dw to <47.1 to 642 (average = 401) pg g-1 dw, followed by perfluorohexanoic acid (PFHxA) (from 38.8 to 219 (average = 162) pg g-1 dw after 15 days and from <20.8 to 161 (average = 101) pg g-1 dw one year later). Together, the hydrodynamics and fire events documented in the region were important features explaining the spread of PFAS.
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Ácidos Alcanossulfônicos , Monitoramento Ambiental , Fluorocarbonos , Poluentes Químicos da Água , Fluorocarbonos/análise , Poluentes Químicos da Água/análise , Ácidos Alcanossulfônicos/análise , Brasil , Sedimentos Geológicos/química , Caproatos/análiseRESUMO
PURPOSE: The management of isolated SLAP lesions is still debated especially in athletes. Aims of the study were: 1. to analyse our algorithm to treat SLAP lesions starting from the selection of patients for surgery and 2. to correlate the familiarity for diabetes and hypothyroid disorders with post-operative results. METHODS: Seventy-eight patients with isolated SLAP lesion were arthroscopically treated using knotless anchors and microfractures. All patients had a pre-operative and post-operative clinical examination according to Walch-Duplay, Constant, Rowe and Dash scores and interviewed for familiarity to diabetes and hypothyroid disorders. RESULTS: About 68.8% of patients solved pain with rehabilitation. About 29% of patients returned to the sports activities. About 32% of patients were no responder to physiotherapy and were arthroscopically treated. About 53.9% of patients responded excellent, 34.7% good, 3.8% medium and 7.6% poor results according to Walch-Duplay score. The Constant score increased from 64 to 95, the Rowe score from 48 to 96. The outcomes were significantly worse in patients with familiarity for diabetes. CONCLUSIONS: Microfractures and knotless anchor give long-term good results for the treatment of SLAP lesions in athletes. The familiarity for diabetes is an important risk factor that can lead to decreased outcomes.
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Diabetes Mellitus , Fraturas de Estresse , Lesões do Ombro , Articulação do Ombro , Traumatismos dos Tendões , Humanos , Fraturas de Estresse/etiologia , Traumatismos dos Tendões/cirurgia , Artroscopia/efeitos adversos , Artroscopia/métodos , Âncoras de Sutura , Fatores de Risco , Articulação do Ombro/cirurgia , Lesões do Ombro/cirurgiaRESUMO
Acmella oleracea (L.) is a plant popularly known as jambu in the Brazilian Amazon. This species has several biological properties, such as anaesthetic, antioxidant and anti-inflammatory activities, among others. However, there is limited information on its anticancer activity. In this context, this study aims to evaluate the effects of the hydroethanolic extract of jambu and its active compound (spilanthol) on gastric cancer cells. Hydroethanolic jambu inflorescence extract was obtained, and spilanthol was isolated by HPLC. Biological cytotoxicity assays were determined using MTT tests. In addition, an in silico study using molecular docking evaluated the inhibitory properties of spilanthol against JAK1 and JAK2 proteins. The results showed that the hydroethanolic extract and the isolated compound spilanthol exhibited cytotoxicity against cancer cells. Molecular docking revealed that spilanthol has inhibitory potential for JAK1 and JAK2 proteins. Thus, extract of jambu and spilanthol can be a possible candidate for the treatment of gastric carcinoma.
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Asteraceae , Neoplasias Gástricas , Humanos , Simulação de Acoplamento Molecular , Alcamidas Poli-Insaturadas , Extratos Vegetais/farmacologiaRESUMO
We measured perfluoroalkyl substances (PFAS) in prey and predator fish from Lake Michigan (USA) to investigate the occurrence and biomagnification of these compounds in this important ecosystem. Twenty-one PFAS were analyzed in 117 prey fish obtained from sites across Lake Michigan and in 87 salmonids collected in four lake quadrants. The mean concentration of sum (∑) PFAS above the method detection limit was 12.7 ± 6.96 ng g-1 wet weight in predator fish (all of which were salmonids) and 10.7 ± 10.4 ng g-1 in prey fish, with outlier levels found in slimy sculpin, Cottus cognatus (187 ± 12.2 ng g-1 ww). Perfluorooctanoic sulfonic acid (PFOS) was the most frequently detected and most abundant compound of the 21 PFAS, occurring in 98 % of individuals with a mean concentration of 9.86 ± 6.36 ng g-1 ww without outliers. Perfluoroalkyl carboxylates (PFCA) concentrations were higher in prey fish than in predators, with some compounds such as perfluorooctanoic acid (PFOA) being detected in higher frequency in prey fish. Besides PFOS, detection of several long-chain (C8-C12) PFCAs were observed in >80 % of the prey fish. Overall, the observed concentrations in Lake Michigan fish were lower than those reported in other Laurentian Great Lakes except for Lake Superior. Biomagnification factors (BMFs) for PFOS exceeded 1.0 (range, 1.80 to 5.12) in all predator-prey relationships analyzed, indicating biomagnification of these compounds, whereas BMFs of other long-chain PFCAs varied according to the fish species. PFAS were found in all fish species measured from Lake Michigan and commonly biomagnified from prey to predator fish, strongly suggesting a dietary connection.
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Ácidos Alcanossulfônicos , Fluorocarbonos , Salmonidae , Poluentes Químicos da Água , Animais , Lagos , Michigan , Ecossistema , Bioacumulação , Peixes , Fluorocarbonos/análise , Ácidos Sulfônicos , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Ácidos Alcanossulfônicos/análiseRESUMO
The construct of "sensory processing sensitivity" has become an extremely popular concept outside the scientific literature under the term "high sensitivity" (HS), reflected in a variety of self-help guides and media reports. Therefore, the present study aimed to investigate this phenomenon by examining in-depth individuals who consider the label HS essential to their self-definition. In semi-structured interviews, 38 individuals described their understanding of HS and its perceived manifestations and impact on their lives (among other topics). Subsequently, the data were content-analytically evaluated, i.e., categorized and quantified. One key finding was that HS individuals feel relief following self-attribution or self-diagnosis. Moreover, this self-attribution replaced the feeling of being somehow different from the others, which almost all interviewees mentioned, with positive attributes. The main negative features of HS mentioned were feeling overwhelmed by sensory and emotional stimuli. The results are discussed with regard to the significance of the label HS for this group on the one hand, and with regard to alternative approaches for future research on the other hand.
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Emoções , Comportamentos Relacionados com a Saúde , Humanos , Autoexame , Pesquisa QualitativaRESUMO
Detection of a gravitational-wave signal of non-astrophysical origin would be a landmark discovery, potentially providing a significant clue to some of our most basic, big-picture scientific questions about the Universe. In this white paper, we survey the leading early-Universe mechanisms that may produce a detectable signal-including inflation, phase transitions, topological defects, as well as primordial black holes-and highlight the connections to fundamental physics. We review the complementarity with collider searches for new physics, and multimessenger probes of the large-scale structure of the Universe.
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Corynebacterium striatum, a common constituent of the human skin microbiome, is now considered an emerging multidrug-resistant pathogen of immunocompromised and chronically ill patients. However, little is known about the molecular mechanisms in the transition from colonization to the multidrug-resistant (MDR) invasive phenotype in clinical isolates. This study performed a comprehensive pan-genomic analysis of C. striatum, including isolates from "normal skin microbiome" and from MDR infections, to gain insights into genetic factors contributing to pathogenicity and multidrug resistance in this species. For this, three novel genome sequences were obtained from clinical isolates of C. striatum of patients from Brazil, and other 24 complete or draft C. striatum genomes were retrieved from GenBank, including the ATCC6940 isolate from the Human Microbiome Project. Analysis of C. striatum strains demonstrated the presence of an open pan-genome (α = 0.852803) containing 3816 gene families, including 15 antimicrobial resistance (AMR) genes and 32 putative virulence factors. The core and accessory genomes included 1297 and 1307 genes, respectively. The identified AMR genes are primarily associated with resistance to aminoglycosides and tetracyclines. Of these, 66.6% are present in genomic islands, and four AMR genes, including aac(6')-ib7, are located in a class 1-integron. In conclusion, our data indicated that C. striatum possesses genomic characteristics favorable to the invasive phenotype, with high genomic plasticity, a robust genetic arsenal for iron acquisition, and important virulence determinants and AMR genes present in mobile genetic elements.
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Antibacterianos , Corynebacterium , Humanos , Fenótipo , Fatores de Virulência/genética , Farmacorresistência Bacteriana Múltipla/genética , Testes de Sensibilidade MicrobianaRESUMO
The neurophysiological investigation of creative idea generation is a growing research area. EEG studies congruently reported the sensitivity of upper alpha power (10-12 Hz) for the creative ideation process and its outcome. However, the majority of studies were between-subject design studies and research directly comparing the neurophysiological activation pattern when generating more and less creative ideas within a person are rare. Therefore, the present study was specifically focused on investigating brain activation patterns associated with the generation of more vs. less creative ideas. We applied an alternate uses task (AU-task; i.e., finding original uses for everyday objects such as a brick) in a sample of 74 participants and recorded the brain activation during the AU-task and reference period. A portable EEG system with 21 dry electrodes arranged in the international 10-20 system and linked ear as reference was used. We found a higher increase of upper alpha power during creative ideation (relative to reference period, i.e., task-related power, TRP) over right posterior sites when people generated more compared to less creative ideas. This was accompanied by an increase of functional coupling (i.e., task-related coherence increase) between frontal and parietal/occipital sites, which suggests higher internal attention and more control over sensory processes. Taken together, these findings complement the existing creativity research literature and indicate the importance of alpha power for the creative ideation process also within people.
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Criatividade , Eletroencefalografia , Atenção , Encéfalo/fisiologia , Mapeamento Encefálico , HumanosRESUMO
Abstract Background: Hereditary angioedema can be caused by C1-Inhibitor (C1-INH) deficiency and/or dysfunction (HAE-1/2) or can occur in patients with normal C1-INH (HAE nC1-INH). Methods: The Icatibant Outcome Survey (IOS; NCT01034969) registry monitors the safety and effectiveness of icatibant for treating acute angioedema. Objective: Present findings from Brazilian patients with HAE-1/2 and HAE nC1-INH participating in IOS. Results: 42 patients were enrolled (HAE-1/2, n = 26; HAE nC1-INH, n = 16). Median age at symptom onset was significantly lower with HAE-1/2 vs. HAE nC1-INH (10.0 vs. 16.5y, respectively; p = 0.0105), whereas median age at diagnosis (31.1 vs. 40.9y; p = 0.1276) and the median time between symptom onset and diagnosis (15.0 vs. 23.8y; p = 0.6680) were numerically lower vs. HAEnC1-INH, respectively. One icatibant dose was used for > 95% of HAE attacks. Median (range) time-to-event outcomes were shorter for patients with HAE nC1-INH vs. HAE-1/2, including time Study limitations: This was an observational study without a treatment comparator and that relied on patient recall. Conclusions: Findings demonstrate effectiveness and tolerability of icatibant in Brazilian HAE patients.
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During the COVID-19 pandemic, the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) Cash Value Benefit (CVB) for fruits and vegetables increased by roughly USD 25/month/person. We sought to understand WIC participant perceptions of this change and barriers and facilitators to using the CVB. We conducted 10 virtual focus groups (5 rural, 5 urban/suburban) with WIC participants (n = 55) in North Carolina in March 2022. Focus groups were recorded and transcribed. We open-coded the content and used thematic analysis to uncover consistencies within and between sampled groups. Participants expressed favorable perceptions of the CVB increase and stated the pre-pandemic CVB amount was insufficient. Barriers to using the increased CVB were identifying WIC-approved fruits and vegetables in stores and insufficient supply of fruits and vegetables. Barriers were more pronounced in rural groups. Facilitators of CVB use were existing household preferences for fruits and vegetables and the variety of products that can be purchased with CVB relative to other components of the WIC food package. Participants felt the CVB increase allowed their families to eat a wider variety of fruits and vegetables. The CVB increase may improve fruit and vegetable intake, particularly if made permanent, but barriers to CVB and WIC benefit use may limit the potential impact.
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COVID-19 , Assistência Alimentar , Criança , Feminino , Frutas , Humanos , Lactente , Pandemias , VerdurasRESUMO
BACKGROUND: Hereditary angioedema can be caused by C1-Inhibitor (C1-INH) deficiency and/or dysfunction (HAE-1/2) or can occur in patients with normal C1-INH (HAE nC1-INH). METHODS: The Icatibant Outcome Survey (IOS; NCT01034969) registry monitors the safety and effectiveness of icatibant for treating acute angioedema. OBJECTIVE: Present findings from Brazilian patients with HAE-1/2 and HAE nC1-INH participating in IOS. RESULTS: 42 patients were enrolled (HAE-1/2, nâ¯=â¯26; HAE nC1-INH, nâ¯=â¯16). Median age at symptom onset was significantly lower with HAE-1/2 vs. HAE nC1-INH (10.0 vs. 16.5y, respectively; pâ¯=â¯0.0105), whereas median age at diagnosis (31.1 vs. 40.9y; pâ¯=â¯0.1276) and the median time between symptom onset and diagnosis (15.0 vs. 23.8y; pâ¯=â¯0.6680) were numerically lower vs. HAE nC1-INH, respectively. One icatibant dose was used for > 95% of HAE attacks. Median (range) time-to-event outcomes were shorter for patients with HAE nC1-INH vs. HAE-1/2, including time to first administration (0.5 [0-96.0] vs. 1.0 [0-94.0]h, respectively), time from first administration to complete resolution (1.0 [0-88.0] vs. 5.5 [0-96.0]h, respectively), and total attack duration (7.0 [0.3-99.0] vs. 18.5 [0.1-100.0]h, respectively). Mean (SD) time from attack onset to resolution was significantly shorter for patients with HAE nC1-INH vs. HAE-1/2 (9.8 [18.7] vs. 19.6 [24.0]h, respectively; pâ¯=â¯0.0174). 83 adverse events (AEs) in 42 patients were reported; most were mild (66.3%) or moderate (13.3%) and non-serious (75.9%). The most common icatibant-related AE was injection site erythema (HAE-1/2, 34.6%; HAE nC1-INH, 18.8%). STUDY LIMITATIONS: This was an observational study without a treatment comparator and that relied on patient recall. CONCLUSIONS: Findings demonstrate effectiveness and tolerability of icatibant in Brazilian HAE patients.
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Angioedemas Hereditários , Bradicinina , Angioedemas Hereditários/diagnóstico , Angioedemas Hereditários/tratamento farmacológico , Bradicinina/análogos & derivados , Bradicinina/uso terapêutico , Brasil , Proteína Inibidora do Complemento C1/química , Humanos , Sistema de Registros , Resultado do TratamentoRESUMO
The aim of the study was to analyze the use of block sequential regularized expectation maximization (BSREM) with different ß-values for the detection of brain metastases in digital fluorine-18 labeled 2-deoxy-2-fluoro-D-glucose (18F-FDG) PET/CT in lung cancer patients. We retrospectively analyzed staging/restaging 18F-FDG PET/CT scans of 40 consecutive lung cancer patients with new brain metastases, confirmed by MRI. PET images were reconstructed using BSREM (ß-values of 100, 200, 300, 400, 500, 600, 700) and OSEM. Two independent blinded readers (R1 and R2) evaluated each reconstruction using a 4-point scale for general image quality, noise, and lesion detectability. SUVmax of metastases, brain background, target-to-background ratio (TBR), and contrast recovery (CR) ratio were recorded for each reconstruction. Among all reconstruction techniques, differences in qualitative parameters were analyzed using non-parametric Friedman test, while differences in quantitative parameters were compared using analysis of variances for repeated measures. Cohen's kappa (k) was used to measure inter-reader agreement. The overall detectability of brain metastases was highest for BSREM200 (R1: 2.83 ± 1.17; R2: 2.68 ± 1.32) and BSREM300 (R1: 2.78 ± 1.23; R2: 2.68 ± 1.36), followed by BSREM100, which had lower accuracy owing to noise. The highest median TBR was found for BSREM100 (R1: 2.19 ± 1.05; R2: 2.42 ± 1.08), followed by BSREM200 and BSREM300. Image quality ratings were significantly different among reconstructions (p < 0.001). The median quality score was higher for BSREM100-300, and both noise and metastases' SUVmax decreased with increasing ß-value. Inter-reader agreement was particularly high for the detectability of photopenic metastases and blurring (all k > 0.65). BSREM200 and BSREM300 yielded the best results for the detection of brain metastases, surpassing both BSREM400 and OSEM, typically used in clinical practice.
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Neoplasias Encefálicas , Neoplasias Pulmonares , Neoplasias Encefálicas/diagnóstico por imagem , Radioisótopos de Flúor , Fluordesoxiglucose F18 , Humanos , Processamento de Imagem Assistida por Computador/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Compostos Radiofarmacêuticos , Estudos RetrospectivosRESUMO
Although the interrupting effect of chronic pain on voluntary-directed attention is well-documented, research on the impact of chronic pain on involuntary-directed attention remains incomplete. This study aimed to investigate the influence of chronic pain on involuntary as well as voluntary allocation of attention as, respectively, indexed by the P3a and P3b components in the event-related potential derived from the electroencephalogram. Both involuntary and voluntary captures of attention were compared between 33 patients with chronic pain and 33 healthy controls using an auditory three-stimulus oddball task (with standard, target, and unexpected distractor tones). The results revealed a reduced P3a amplitude as well as a reduced P3b amplitude in patients with chronic pain compared to healthy controls, indicating a detrimental effect of chronic pain on involuntary and voluntary attention, respectively. This study extends the picture of the impairing effects of chronic pain on attentional allocation to a current task and attentional allocation to information outside the focus of attention. (PsycInfo Database Record (c) 2022 APA, all rights reserved).
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Dor Crônica , Atenção , Eletroencefalografia , Potenciais Evocados , HumanosRESUMO
PURPOSE: Dynamic testing represents the mainstay in the differential diagnosis of ACTH-dependent Cushing's syndrome. However, in case of undetectable or detectable lesion < 6 mm on MRI, bilateral inferior petrosal sinus sampling (BIPSS) is suggested by current guidelines. Aim of this study was to analyze the performance of CRH, desmopressin and high-dose dexamethasone suppression test (HDDST) in the differential diagnosis of ACTH-dependent Cushing's syndrome as well as the impact of invasive and noninvasive tests on surgical outcome in patients affected by Cushing's disease (CD). METHODS: Retrospective analysis on 148 patients with CD and 26 patients with ectopic ACTH syndrome. RESULTS: Among CD patients, negative MRI/lesion < 6 mm was detected in 97 patients (Group A); 29 had a 6-10 mm lesion (Group B) and 22 a macroadenoma (Group C). A positive response to CRH test, HDSST and desmopressin test was recorded in 89.4%, 91·4% and 70.1% of cases, respectively. Concordant positive response to both CRH/HDDST and CRH/desmopressin tests showed a positive predictive value of 100% for the diagnosis of CD. Among Group A patients with concordant CRH test and HDDST, no difference in surgical outcome was found between patients who performed BIPSS and those who did not (66.6% vs 70.4%, p = 0.78). CONCLUSIONS: CRH, desmopressin test and HDDST have high accuracy in the differential diagnosis of ACTH-dependent CS. In patients with microadenoma < 6 mm or non-visible lesion, a concordant positive response to noninvasive tests seems sufficient to diagnose CD, irrespective of MRI finding. In these patients, BIPSS should be reserved to discordant tests.
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Hormônio Adrenocorticotrópico/sangue , Síndrome de Cushing/diagnóstico , Imageamento por Ressonância Magnética/métodos , Amostragem do Seio Petroso/métodos , Hipersecreção Hipofisária de ACTH , Testes de Função Hipofisária/métodos , Neoplasias Hipofisárias , Adulto , Síndrome de Cushing/epidemiologia , Diagnóstico Diferencial , Técnicas de Diagnóstico Endócrino , Feminino , Humanos , Hipofisectomia/métodos , Hipofisectomia/estatística & dados numéricos , Itália/epidemiologia , Masculino , Hipersecreção Hipofisária de ACTH/sangue , Hipersecreção Hipofisária de ACTH/diagnóstico , Hipersecreção Hipofisária de ACTH/epidemiologia , Hipersecreção Hipofisária de ACTH/cirurgia , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/patologia , Neoplasias Hipofisárias/cirurgia , Estudos RetrospectivosRESUMO
BACKGROUND AND AIM: The BRCA 1 and BRCA 2 genes are associated with an inherited susceptibility to breast cancer with a cumulative risk of 60% in BRCA 1 mutation carriers and of 30% in BRCA 2 mutation carriers. Several lifestyle factors could play a role in determining an individual's risk of breast cancer. Obesity, changes in body size or unhealthy lifestyle habits such as smoking, alcohol consumption and physical inactivity have been evaluated as possible determinants of breast cancer risk. The aim of this study was to explore the current understanding of the role of harmful lifestyle and obesity or weight change in the development of breast cancer in female carriers of BRCA 1/2 mutations. METHODS: Articles were identified from MEDLINE in October 2020 utilizing related keywords; they were then read and notes, study participants, measures, data analysis and results were used to write this review. RESULTS: Studies with very large case series have been carried out but only few of them have shown consistent results. Additional research would be beneficial to better determine the actual role and impact of such factors.
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The present study investigated the effects of plyometric jump training on hard and soft surfaces on running economy (RE), maximal oxygen uptake (VO2max), running performance and the rate of force development in orienteers. Nineteen orienteers (11 women and 8 men, body mass 61.1 ± 7.3 kg, age 21 ± 5.8 yrs) were randomly stratified based on sex, age, VO2max and RE to plyometric jumping training (8 sessions over 4 weeks) on either a hard or a soft surface. RE, VO2max and running performance were assessed on a treadmill and outdoor on- and off-trail loops. Moreover, ground reaction forces and force development were assessed during a one leg drop-jump test. The training intervention led to an overall 2-7% improvement in treadmill and off-trail RE, independent of the jumping surface and running velocity assessed. These improvements were not explained by force development during drop jump tests, which remained unchanged following the intervention. The changes in time-trial performance were associated with changes in RE. Plyometric training improved RE with no difference between the hard or the soft training surface and improved RE was also independent of the running speed assessed. Furthermore, improved running performance was associated with changes in RE after the intervention.
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The maintenance of healthy and functional mitochondria is the result of a complex mitochondrial turnover and herein quality-control program that includes both mitochondrial biogenesis and autophagy of mitochondria. The aim of this study was to examine the effect of an intensified training load on skeletal muscle mitochondrial quality control in relation to changes in mitochondrial oxidative capacity, maximal oxygen consumption, and performance in highly trained endurance athletes. Elite endurance athletes (n = 27) performed high-intensity interval exercise followed by moderate-intensity continuous exercise 3 days per week for 4 wk in addition to their usual volume of training. Mitochondrial oxidative capacity, abundance of mitochondrial proteins, markers of autophagy, and antioxidant capacity of skeletal muscle were assessed in skeletal muscle biopsies before and after the intensified training period. The intensified training period increased several autophagy markers suggesting an increased turnover of mitochondrial and cytosolic proteins. In permeabilized muscle fibers, mitochondrial respiration was â¼20% lower after training although some markers of mitochondrial density increased by 5%-50%, indicative of a reduced mitochondrial quality by the intensified training intervention. The antioxidative proteins UCP3, ANT1, and SOD2 were increased after training, whereas we found an inactivation of aconitase. In agreement with the lower aconitase activity, the amount of mitochondrial LON protease that selectively degrades oxidized aconitase was doubled. Together, this suggests that mitochondrial respiratory function is impaired during the initial recovery from a period of intensified endurance training whereas mitochondrial quality control is slightly activated in highly trained skeletal muscle.NEW & NOTEWORTHY We show that mitochondrial respiration is temporarily impaired after a period of intensified exercise training in elite athletes. In parallel, proteins involved in the antioxidative response including SOD2, UCP3, and ANT2 were upregulated, whereas mitochondrial biogenesis was slightly activated. Despite the mitochondrial respiratory impairments, physical performance was improved a few days after the intense training period.
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Mitocôndrias Musculares , Resistência Física , Atletas , Humanos , Mitocôndrias , Mitocôndrias Musculares/metabolismo , Músculo Esquelético/metabolismo , Consumo de OxigênioRESUMO
We present briefly the LLAMA sub-mm radiotelescope, a joint project of Argentina and Brazil, being mounted in the Andes, Argentina, at 4800 m altitude. Here we focus on the activities that are going on mostly under the responsibility of Brazil, like the high frequency receivers, parts of the back-end and electronics, the optical system of the telescope to bring the radiation to the receivers, the equipment needed for the integration and verification phase (optical telescope and holography) and the computation system.The main scientific applications that are planned are dscribed. We also report on a joint program with BRICS countries approved in 2019, which will involve the use of LLAMA for testing high-frequency receivers.