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1.
Phys Chem Chem Phys ; 24(26): 16228-16236, 2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35758065

RESUMO

A better understanding of the effects of temperature and pressure on the wide gap SiC semiconductor is necessary for both (i) an improvement of the performance of this compound in a variety of technological applications and (ii) a clarification of controversial issues related to the stability of its cubic polymorphs at high pressure and high temperature. Bearing in mind this double demand, we perform first-principles calculations of the phonon band structures, vibrational density of states, and thermal and mode Grüneisen parameters of the zinc blende (B3) and rock-salt (B1) cubic polymorphs of 3C-SiC covering pressures and temperatures up to 120 GPa and 3000 K, respectively. Under a martensitic description of the B3-B1 transformation, we found that the large hysteresis pressure range observed at room temperature (35-100 GPa) disappears at around 1100 K. The calculated Clapeyron slope of this transformation is slightly negative, with average values of -2.9 MPa K-1 in the 0-3000 K interval and -3.7 MPa K-1 at 2000 K. We also study the decomposition reaction of the two cubic polymorphs into their elemental constituents (C and Si), finding a decreasing (increasing) decomposition temperature for the B3 (B1) phase as the pressure is applied. All these results are sustained by good agreement with other recently reported experimental and theoretical thermodynamic data that have also been evaluated under our quasi-harmonic approximation framework.

2.
J Sleep Res ; 30(3): e13165, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32812310

RESUMO

Cardiac death is the second most prevalent cause in Prader-Willi syndrome (PWS). Paediatric patients with PWS often present cardiac autonomic dysfunction during wakefulness, obesity and sleep-disordered breathing. However, the extent of cardiac autonomic modulation during sleep in PWS has not been documented. The objective of this study was to assess alterations in cardiac autonomic modulation of paediatric patients with PWS during different sleep stages. Thirty-nine participants in three groups: 14 PWS, 13 sex and age-matched lean controls (LG) and 12 obese-matched controls (OB). All participants underwent overnight polysomnography, including continuous electrocardiogram recordings. Heart rate variability (HRV) was analysed during representative periods of each sleep stage through time and frequency domains calculated across 5-min periods. Between-within ANOVAs were employed (p < .05). The results show that total HRV was lower in PWS than OB and LG during slow-wave sleep (SWS) (standard deviation of all NN intervals [SDNN] ms, p = .006). Parasympathetic modulation assessed by time-domain analysis was lower during SWS in PWS compared to both OB and LG (square root of the mean of the sum of the squares of differences between adjacent NN intervals [RMSSD] ms, p = .004; SDSD, standard deviation of differences between adjacent NN intervals [SDSD] ms, p = .02; number of adjacent NN intervals differing by >50 ms [NN50] ms, p = .03; proportion of adjacent NN intervals differing by >50 ms [pNN50] ms, p = .01). Sympathovagal balance assessed by frequency-domain analysis was lower during both N2 and SWS than during the rapid eye movement (REM) sleep stage, but not different among groups. In conclusion, this group of paediatric patients with PWS had impaired cardiac autonomic balance due to reduced parasympathetic modulation during SWS. This result could imply an underlying increased cardiovascular risk in PWS even during early age and independent of obesity.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Eletrocardiografia/métodos , Polissonografia/métodos , Síndrome de Prader-Willi/fisiopatologia , Fases do Sono/fisiologia , Adolescente , Criança , Feminino , Humanos , Masculino
3.
Inorg Chem ; 60(3): 1746-1754, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33449624

RESUMO

The quest for new transition metal dichalcogenides (TMDs) with outstanding electronic properties operating under ambient conditions draws us to investigate the 1T-HfSe2 polytype under hydrostatic pressure. Diamond anvil cell (DAC) devices coupled to in situ synchrotron X-ray, Raman, and optical (VIS-NIR) absorption experiments along with density functional theory (DFT)-based calculations prove that (i) bulk 1T-HfSe2 exhibits strong structural and vibrational anisotropies, being the interlayer direction especially sensitive to pressure changes, (ii) the indirect gap of 1T-HfSe2 tends to vanish by a -0.1 eV/GPa pressure rate, slightly faster than MoS2 or WS2, (iii) the onset of the metallic behavior appears at Pmet ∼10 GPa, which is to date the lowest pressure among common TMDs, and finally, (iv) the electronic transition is explained by the bulk modulus B0-Pmet correlation, along with the pressure coefficient of the band gap, in terms of the electronic overlap between chalcogenide p-type and metal d-type orbitals. Overall, our findings identify 1T-HfSe2 as a new efficient TMD material with potential multipurpose technological applications.

4.
J ECT ; 37(1): 58-63, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33009217

RESUMO

BACKGROUND: Given the limited therapeutic options for Prader-Willi syndrome (PWS), we conducted an open-label clinical trial to evaluate the effects of transcranial direct current stimulation (tDCS) for hyperphagia, food craving, and aberrant behaviors on this population. METHODS: Twelve subjects with PWS (11-35 years old) were included. The subjects underwent 10 daily 20-minute sessions of tDCS in 2 weeks. The anode was positioned over the left dorsolateral prefrontal cortex, and the cathode over the contralateral region. RESULTS: We observed amelioration of hyperphagic and food craving symptoms (P < 0.05), as well as amelioration of behavioral symptoms measured with the Aberrant Behavior Checklist (P < 0.05). DISCUSSION: To our knowledge, this is the first proof-of-concept trial to report the positive effects of increasing excitability of the left dorsolateral prefrontal cortex, using tDCS, for the behavioral, hyperphagia, and food craving symptoms in PWS, which is a low-cost, well-studied, safe alternative for brain stimulation.


Assuntos
Síndrome de Prader-Willi/terapia , Estimulação Transcraniana por Corrente Contínua , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
5.
Phys Chem Chem Phys ; 22(38): 21909-21918, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-32969437

RESUMO

AM2X4 crystalline materials display important technological electronic, optical and magnetic properties that are sensitive to general stress effects. In this paper, the behavior under hydrostatic pressure of the ambient condition rhombohedral phase of MgIn2Se4 is investigated in detail for the first time. We carried out first-principles calculations within the density functional theory framework aimed at determining the pressure-induced polymorphic sequence of this selenide. To accurately evaluate transition pressures at room temperature, thermal corrections have been included after the computation of phonon dispersion curves in potential candidate phases, namely the initial rhombohedral R3[combining macron]m one, inverse and direct spinels, LiTiO2-type and defective I4[combining macron] structures. Only the transition from the R3[combining macron]m to the inverse spinel phase was found to fulfill the thermodynamic and mechanical stability criteria. The direct spinel could appear as metastable if kinetic effects hinder the above transition. Additionally, electronic band structures and chemical bonding properties were analyzed from the outcome of our quantum-mechanical solutions reporting band gap values and ionicity and noncovalent interaction indexes. It is shown that the investigated compound keeps behaving as a semiconductor, loses its van der Waals interactions, and becomes more covalent as hydrostatic pressure is applied.

6.
Gynecol Endocrinol ; 34(1): 45-48, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28758509

RESUMO

BACKGROUND AND AIMS: In adolescence and obesity, the pathophysiology of polycystic ovary syndrome (PCOS) is very difficult to distinguish. We aimed to assess the diagnosis of PCOS in the population of obese adolescent. METHODS: Cross-sectional study. SETTING: Pediatric Endocrinology Weight and Management Clinic from Children's Institute, São Paulo, Brazil. PARTICIPANTS: Forty-nine post-menarcheal obese adolescents with mean age of 14.7 years. INTERVENTIONS: Anthropometric assessment and review of medical records were done. Clinical and laboratory hyperandrogenism were quantified using Ferriman-Gallwey index and androgenic dosages, respectively. Ovarian morphology was evaluated through suprapubic ultrasonography. RESULTS: By the 2015 Witchel et al. guideline for PCOS in adolescence, 18.4% were diagnosed as having PCOS. When assessed by Rotterdam, Androgen Excess and PCOS Society, and American National Institute of Health criteria's, 26.4%, 22.4%, and 20.4% had PCOS, respectively. Irregular menstrual cycles were found in 65.3% of patients. Clinical hyperandrogenism was observed in 16.3% of girls and 18.4% had elevated serum androgen values. Suprapubic ultrasonography revealed enlarged ovaries in 18.4% of the adolescents. CONCLUSIONS: PCOS in all-comers obese adolescents from a Weight and Management Clinic in a quaternary hospital is more frequent when compared to adult women showed in the literature.


Assuntos
Obesidade/complicações , Obesidade/epidemiologia , Ovário/diagnóstico por imagem , Síndrome do Ovário Policístico/diagnóstico , Síndrome do Ovário Policístico/epidemiologia , Adolescente , Androgênios/sangue , Índice de Massa Corporal , Brasil/epidemiologia , Estudos Transversais , Feminino , Humanos , Hiperandrogenismo/diagnóstico , Distúrbios Menstruais/complicações , Distúrbios Menstruais/epidemiologia , National Institutes of Health (U.S.) , Síndrome do Ovário Policístico/complicações , Ultrassonografia , Estados Unidos
7.
Dalton Trans ; 53(9): 4266-4277, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38344781

RESUMO

Identifying and evaluating novel and extremely stable materials for catalysis is one of the major challenges that mankind faces today to rapidly reduce the dependence on fossil fuels. To contribute to achieving this goal, we have evaluated within the density-functional framework the properties of a new two-dimensional MXene structure, the asymmetric MXene YZrCOF monolayer. Phonon dispersion calculations at 0 K and 300 K indicate that the studied material is dynamically stable. The calculations also indicate that the material has a rigid crystal structure with a wide band gap, a strong potential difference, and a band-gap alignment that favors the production of both H2 and O2 molecules from water splitting. We also report the outcome of the strain effect on the electrical and photocatalytic characteristics of the studied material. We will demonstrate that even under a large strain, the YZrCOF monolayer is stable and useful for photocatalytic applications.

8.
Front Endocrinol (Lausanne) ; 15: 1403470, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38966214

RESUMO

Introduction: Prader-Willi syndrome (PWS) is a genetic disorder characterized by hypothalamic-pituitary deficiencies including hypogonadism. In girls with PWS, hypogonadism can present early in childhood, leading to genital hypoplasia, delayed puberty, incomplete pubertal development, and infertility. In contrast, girls can present with premature activation of the adrenal axis leading to early pubarche and advanced bone age. We aim to evaluate the progression of puberty and adrenarche signals in girls with PWS. Methodology: A longitudinal retrospective cohort study included girls with PWS followed at a Pediatric Endocrinology Outpatient Clinic in a Tertiary University Hospital in Sao Paulo, Brazil from 2002 to 2022. Data collected via chart review included clinical information on birth history, breast and pubic hair Tanner stages, presence of genital hypoplasia, age at menarche, regularity of menstrual cycles, body mass index (BMI) z-score, final height, age of initiation of estrogen replacement and growth hormone replacement, as well as results for PWS genetic subtype; biochemical investigation (LH, FSH, estradiol, DHEA-S); radiographic bone age and pelvic ultrasound. Results: A total of 69 girls were included in the study and the mean age of puberty onset was 10.2 years in those who started puberty after the age of 8 years. Breast Tanner stage IV was reached by 29.1% girls at a mean age of 14.9 years. Spontaneous menarche was present in 13.8% and only one patient had regular menstrual cycles. Early adrenarche was seen in 40.4% of cases. Conclusion: Our study demonstrated in a large sample that girls with PWS often present with delayed onset of puberty despite frequent premature adrenarche. Based on our results, we suggest an estrogen replacement protocol for girls with PWS to be started at the chronological age or bone age of 12-13 years, taking into consideration the uterus size. Further prospective studies are needed.


Assuntos
Síndrome de Prader-Willi , Puberdade , Humanos , Feminino , Síndrome de Prader-Willi/fisiopatologia , Criança , Estudos Retrospectivos , Adolescente , Puberdade/fisiologia , Estudos Longitudinais , Centros de Atenção Terciária , Menarca/fisiologia , Brasil/epidemiologia , Estudos de Coortes , Adrenarca , Puberdade Precoce/epidemiologia
9.
PLoS One ; 18(7): e0287822, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37498887

RESUMO

Prior studies suggest that one anticipated benefit of bariatric surgery is the achievement of a thinner body, one that is less subject to perceived negative judgment and condemnation by others. However, additional analyses also indicate that stigma may persist even with significant post-surgery weight loss. To investigate the stigma-related perceptions and experiences of women who have undergone bariatric surgery and the resulting body transformations, we conducted individual, semi-structured interviews with thirty Brazilian women (15 aged 33-59 and 15 aged 63-72). The resulting text was then analyzed using thematic analysis. We found that some form of weight stigma persisted for our participants, regardless of weight loss. Ongoing experiences of stigma were also evidenced by the constant internal and external vigilance reported by the women, as well as their articulated efforts to distance themselves from their previous bodies. Additionally, participants reported being judged for choosing an "easy way out" to lose weight. Those in the older group reported that weight stigma was entangled with ageism: older participants received mixed messages underscoring the ways that weight and age may interact in doubly stigmatizing ways. Family and close peers were especially powerful sources of stigma experiences. Collectively, these results show that weight stigma persists even when people undergo a procedure to lose substantive weight and that the degree and types of stigma experiences are influenced by gender and age. Our study suggest future research should explore whether a targeted approach might be more effective, for example, an approach that would emphasize the importance of developing coping strategies with respect to experiences of stigma and discrimination after surgery.


Assuntos
Cirurgia Bariátrica , Preconceito de Peso , Humanos , Feminino , Brasil , Estigma Social , Pesquisa Qualitativa
10.
Arch Endocrinol Metab ; 65(5): 527-536, 2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34591402

RESUMO

Obesity is a complex and multifactorial disease that is influenced by physiological, environmental, socioeconomic, and genetic factors. In recent decades, this serious disease has impacted a large number of adolescents as a result of lifestyle factors. A lack of exercise and the consumption of excessive calories from an inadequate diet are the main contributors to adolescent obesity. However, genetic and hormonal factors might also play a role. The short- and long-term consequences of this disease include chronic issues such as type 2 diabetes and cardiovascular disorders and an increase in early mortality rates. Although it is a serious disease, obesity in adolescents can be controlled with diet and exercise. When these lifestyle changes do not obtain the expected results, we can intensify the treatment by adding medication to the practice of diet and exercise. Additionally, for more severe cases, bariatric surgery can be an option. The purpose of this review is to clarify the current epidemiology, risks, and comorbidities and discuss news about the main treatments and the necessary improvements in this context.


Assuntos
Diabetes Mellitus Tipo 2 , Obesidade Infantil , Adolescente , Dieta , Exercício Físico , Humanos , Estilo de Vida , Obesidade Infantil/epidemiologia , Obesidade Infantil/terapia
11.
Horm Res Paediatr ; 94(11-12): 410-415, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34610594

RESUMO

BACKGROUND/AIMS: Obesity leads to increased risk of thromboembolic events in adults, but few studies have addressed the relationship between obesity and thrombogenic risk during childhood. The aim of this study was to evaluate the prothrombotic state of obese children in comparison with healthy children. METHODS: Thrombin generation, fibrinogen, and D-dimer levels, along with metabolic parameters, were measured in 72 prepubertal children, of which 47 were obese and 25 eutrophic. RESULTS: A significant increase in thrombin generation, fibrinogen, and dyslipidemia was found among obese patients. CONCLUSION: A prothrombotic state develops in childhood obesity during the prepubertal phase.


Assuntos
Doenças Cardiovasculares , Obesidade Infantil , Adulto , Índice de Massa Corporal , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Criança , Fibrinogênio/análise , Fibrinogênio/metabolismo , Fatores de Risco de Doenças Cardíacas , Humanos , Obesidade Infantil/complicações , Fatores de Risco
12.
Clinics (Sao Paulo) ; 76: e3501, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34817047

RESUMO

OBJECTIVE: To assess the possible factors that influence sleep quality in adolescents with and without chronic immunosuppressive conditions quarantined during the coronavirus disease 2019 (COVID-19) pandemic. METHODS: This cross-sectional study included 305 adolescents with chronic immunocompromised conditions and 82 healthy adolescents. Online surveys were completed, which included questions on socio-demographic data and self-rated healthcare routine during COVID-19 quarantine and the following validated questionnaires: the Pittsburgh Sleep Quality Index (PSQI), Pediatric Quality of Life Inventory 4.0 (PedsQL4.0), and Pediatric Outcome Data Collection Instrument (PODCI). RESULTS: The median current age [14 (10-18) vs. 15 (10-18) years, p=0.847] and frequency of female sex (62% vs. 58%, p=0.571) were similar in adolescents with chronic conditions compared with healthy adolescents. The frequency of poor sleep quality was similar in both groups (38% vs. 48%, p=0.118). Logistic regression analysis, including both healthy adolescents and adolescents with chronic conditions (n=387), demonstrated that self-reported increase in screen time (odds ratio [OR] 3.0; 95% confidence interval [CI] 1.3-6.8; p=0.008) and intrafamilial violence report (OR 2.1; 95% CI 1.2-3.5; p=0.008) were independently associated with poor sleep quality in these adolescents. However, the PODCI global function score was associated with a lower OR for poor sleep quality (OR 0.97; 95% CI 0.94-0.99; p=0.001). Further logistic regression, including only adolescents with chronic conditions (n=305), demonstrated that self-reported increase in screen time (OR 3.1; 95% CI 1.4-6.8; p=0.006) and intrafamilial violence report (OR 2.0; 95% CI 1.2-3.4; p=0.011) remained independently associated with poor quality of sleep, whereas a lower PODCI global function score was associated with a lower OR for sleep quality (OR 0.96; 95% CI 0.94-0.98; p<0.001). CONCLUSION: Self-reported increases in screen time and intrafamilial violence report impacted sleep quality in both healthy adolescents and those with chronic conditions. Decreased health-related quality of life was observed in adolescents with poor sleep quality.


Assuntos
COVID-19 , Qualidade de Vida , Adolescente , Criança , Doença Crônica , Estudos Transversais , Feminino , Humanos , Quarentena , SARS-CoV-2 , Sono , Inquéritos e Questionários
13.
Arch Endocrinol Metab ; 64(3): 223-234, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32555988

RESUMO

Prader-Willi syndrome (PWS) is a genetic disorder caused by the absence of gene expression in the 15q11.2-q13 paternal chromosome. Patients with PWS develop hypothalamic dysfunction that can lead to various endocrine changes such as: obesity, growth hormone deficiency, hypogonadism, hypothyroidism, adrenal insufficiency and low bone mineral density. In addition, individuals with PWS have increased risk of developing type 2 diabetes mellitus. This review summarizes and updates the current knowledge about the prevention, diagnosis and treatment of endocrine manifestations associated with Prader Willi syndrome, especially diagnosis of growth hormone deficiency, management and monitoring of adverse effects; diagnosis of central adrenal insufficiency and management in stressful situations; screening for central hypothyroidism; research and treatment of hypogonadism; prevention and treatment of disorders of glucose metabolism. Careful attention to the endocrine aspects of PWS contributes significantly to the health of these individuals. Arch Endocrinol Metab. 2020;64(3):223-34.


Assuntos
Síndrome de Prader-Willi , Diabetes Mellitus/etiologia , Humanos , Hipogonadismo/etiologia , Hipotireoidismo/etiologia , Obesidade/etiologia , Síndrome de Prader-Willi/complicações , Síndrome de Prader-Willi/diagnóstico , Síndrome de Prader-Willi/genética
14.
J Pediatr Endocrinol Metab ; 33(3): 397-401, 2020 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-32069243

RESUMO

Background This study aimed to investigate the presence of sleep disturbances in children with Prader-Willi syndrome (PWS) using the Sleep Disturbance Scale for Children (SDSC). Methods The SDSC, which was designed to identify the presence and severity of different sleep disorders, was applied to 50 patients with PWS and 112 controls. Results Patients with PWS achieved worse scores in the sleep-disordered breathing and disorders in initiating and maintaining sleep in the SDSC questionnaire as compared with controls. We also observed that patients with PWS were more prone to having hyperhidrosis. We did not observe significant differences in the presence of other types of sleep disorders (such as hypersomnolence) between the PWS and control groups. Conclusions The results obtained with the SDSC questionnaire showed that children with PWS have more sleep breathing disorders and disorders in initiating and maintaining sleep as compared to controls. Additionally, we demonstrated that patients with PWS associates significantly with the presence of hyperhidrosis during sleep. However, SDSC was not reliable to identify the excessive daytime somnolence in patients with PWS, as previously reported in the literature.


Assuntos
Síndrome de Prader-Willi/complicações , Transtornos do Sono-Vigília/etiologia , Inquéritos e Questionários , Adolescente , Criança , Pré-Escolar , Distúrbios do Sono por Sonolência Excessiva/complicações , Feminino , Humanos , Hiperidrose/complicações , Masculino , Síndromes da Apneia do Sono/etiologia , Distúrbios do Início e da Manutenção do Sono/etiologia
15.
BMJ Paediatr Open ; 4(1): e000630, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32411831

RESUMO

BACKGROUND: Growth hormone (GH) treatment is currently recommended in Prader-Willi syndrome (PWS) patients. OBJECTIVES: To evaluate the impact (efficacy and safety) of the use of recombinant human GH (rhGH) as a treatment for PWS. METHOD: We performed a systematic review and, where possible, meta-analysis for the following outcomes: growth, body mass index, body composition, cognitive function, quality of life, head circumference, motor development/strength, behaviour and adverse effects. We included all PWS patients, with all types of genetic defects and with or without GH deficiency, who participated in rhGH studies performed in infancy, childhood and adolescence, that were either randomised controlled trials (RCTs) (double-blinded or not) or non-randomised controlled trials (NRCTs) (cohort and before and after studies). The databases used were MEDLINE, Embase and Cochrane Central. RESULTS: In 16 RCTs and 20 NRCTs selected, the treated group had an improvement in height (1.67 SD scores (SDS); 1.54 to 1.81); body mass index z-scores (-0.67 SDS; -0.87 to -0.47) and fat mass proportion (-6.5% SDS; -8.46 to -4.54) compared with the control group. Data about cognition could not be aggregated. Conclusion Based on high quality evidence, rhGH treatment favoured an improvement of stature, body composition and body mass index, modifying the disease's natural history; rhGH treatment may also be implicated in improved cognition and motor development in PWS patients at a young age. ETHICS AND DISSEMINATION: The current review was approved by the ethical committee of our institution. The results will be disseminated through conference presentations and publications in peer-reviewed journals. PROSPERO REGISTRATION NUMBER: CRD42019140295.

16.
Rev Paul Pediatr ; 38: e2018239, 2020.
Artigo em Inglês, Português | MEDLINE | ID: mdl-31939513

RESUMO

OBJECTIVE: To describe a case of a male adolescent with symptomatic idiopathic intracranial hypertension (IIH) associated with obesity treated with bariatric surgery. CASE DESCRIPTION: A 16-year-and-6-month-old severely obese boy [weight: 133.6 kg; height: 1.74 m (Z score: +0.14); BMI: 44.1 kg/m2 (Z score: +4.4)], Tanner pubertal stage 5, presented biparietal, high-intensity, and pulsatile headaches, about five times per week, associated with nocturnal awakenings, and partial improvement with common analgesics, for three months. Ophthalmologic evaluation evidenced bilateral papilledema. Cranial computed tomography revealed no mass or anatomic abnormalities. Lumbar puncture showed increased intracranial pressure of 40 cmH2O (reference value: <28 cmH2O) with a normal content. After being diagnosed with IIH, the patient was started on acetazolamide. However, after three months, he was still symptomatic. He was diagnosed with obesity due to excess energy intake and, as he had failed to lose weight after a conventional clinical treatment, bariatric surgery was indicated. The patient (at 16 years and nine months) underwent an uncomplicated laparoscopic sleeve gastrectomy. Ophthalmologic evaluation, performed five months after surgery, revealed normal visual acuity in both eyes and improvement of bilateral papilledema. Follow-up at 18 months showed a 67.5% loss of excess weight (weight: 94.5 kg and BMI: 31.2 kg/m2) and complete resolution of IIH symptoms. COMMENTS: IIH is characterized by increased intracranial pressure with no evidence of deformity or obstruction of the ventricular system on neuroimaging. It has been associated with obesity. Bariatric surgery may be a valid alternative approach for morbidly obese adolescent patients with refractory symptoms.


Assuntos
Cirurgia Bariátrica/métodos , Obesidade Mórbida/cirurgia , Pseudotumor Cerebral/fisiopatologia , Acetazolamida/uso terapêutico , Adolescente , Assistência ao Convalescente , Diuréticos/uso terapêutico , Fundo de Olho , Cefaleia/diagnóstico , Cefaleia/etiologia , Humanos , Masculino , Papiledema/diagnóstico por imagem , Pseudotumor Cerebral/diagnóstico , Pseudotumor Cerebral/tratamento farmacológico , Punção Espinal/métodos , Resultado do Tratamento , Redução de Peso/fisiologia
17.
Nanomaterials (Basel) ; 9(10)2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31635297

RESUMO

Understanding the stability limit of crystalline materials under variable tensile stress conditions is of capital interest for technological applications. In this study, we present results from first-principles density functional theory calculations that quantitatively account for the response of selected covalent and layered materials to general stress conditions. In particular, we have evaluated the ideal strength along the main crystallographic directions of 3C and 2H polytypes of SiC, hexagonal ABA stacking of graphite and 2H-MoS 2 . Transverse superimposed stress on the tensile stress was taken into account in order to evaluate how the critical strength is affected by these multi-load conditions. In general, increasing transverse stress from negative to positive values leads to the expected decreasing of the critical strength. Few exceptions found in the compressive stress region correlate with the trends in the density of bonds along the directions with the unexpected behavior. In addition, we propose a modified spinodal equation of state able to accurately describe the calculated stress-strain curves. This analytical function is of general use and can also be applied to experimental data anticipating critical strengths and strain values, and for providing information on the energy stored in tensile stress processes.

18.
Curr Obes Rep ; 7(2): 97-104, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29737493

RESUMO

PURPOSE OF REVIEW: The purpose of this study is to present changes of policies and norms aimed to reduce obesity levels that have been adopted in some Latin American countries. RECENT FINDINGS: The global increase of the excess weight within the population has been demanding governmental actions aimed at preventing health impacts generated by obesity. Over recent years, many Latin American countries have established a number of regulations aimed at reducing weight in the population using interventions that could effectively prevent childhood obesity, including the taxation of sugar-sweetened beverages (SSBs), increasing physical activity in open spaces, and, especially, front-of-package labeling. Some strategies are part of the Action Plan for Prevention of Child and Adolescence Obesity signed by all countries in Latin America, which currently have among the highest prevalence of childhood obesity in the world. Among them are the implementation of fiscal policies on energy-dense and nutrient-poor foods and taxes on SSBs; improvements in nutrition labeling, highlighting the front-of-package (FOP) labeling to promote the choice of healthier products at the time of purchase; and promotion of an active lifestyle, such as encouraging the use of bicycle paths or physical activity programs at school. The real impact of these prevention strategies implemented in Latin America on the prevalence of obesity is still unknown.


Assuntos
Promoção da Saúde/métodos , Obesidade/prevenção & controle , Políticas , Dieta , Exercício Físico , Rotulagem de Alimentos , Humanos , América Latina/epidemiologia , Obesidade/epidemiologia , Obesidade Infantil/epidemiologia , Obesidade Infantil/prevenção & controle , Impostos
19.
Psico (Porto Alegre) ; 54(2): 40413, 2023.
Artigo em Português | LILACS | ID: biblio-1554804

RESUMO

Pais e cuidadores de crianças com a síndrome Prader-Willi (SPW) enfrentam desafios no manejo dos comportamentos característicos do fenótipo comportamental dessa condição, que demandam habilidades parentais que nem sempre fazem parte do seu repertório, o que torna necessário um treino específico. O objetivo do presente estudo foi aplicar e avaliar o Programa de Qualidade na Interação Familiar (PQIF) para pais de crianças com SPW. Sete participantes associados ao ambulatório de SPW do Hospital das Clínicas de São Paulo (ICr-HCFMUSP) participaram do estudo, e medidas foram aplicadas nas fases pré, pós e follow-up. O escore de estilo parental demonstrou aumento no uso de práticas parentais positivas para seis dos sete participantes. Os participantes também apresentaram melhora na auto-observação, ampliação no repertório de análise de comportamentos e de manejo adequado. Limites deste estudo são discutidos, contudo, os dados reforçam a importância de se validar ferramentas que atendam essa população


Parents and relatives of children with Prader-Willi Syndrome (PWS) face challenges in managing behaviors characteristic of the behavioral pheno-type of this condition, which require specific parental skills, that are not always part of their repertoire, and therefore training. The aim of the present study was to apply and evaluate the Family Interaction Quality Program (PQIF) for parents of children with PWS. Seven participants associated to the PWS outpatient clinic of the ICr-HCFMUSP took apart in the study, and measures were applied in the pre, post and follow-up phases. The parenting style score demonstrated an increased use of positive parenting practices for six of the seven participants. Participants also showed improvements in self-observation, expansions in the repertoire of analysis of behaviors and appropriate handling. Limits of this study are discussed; however, the data reinforce the importance of validating tools that attend this population


Los padres y cuidadores de niños con Síndrome de Prader-Willi (SPW) enfrentan desafíos en el manejo de conductas difíciles, propias del fenotipo conductual de esta condición, que demandan habilidades parentales y capacitación específicas. El objetivo del presente estudio fue aplicar y evaluar el Programa de Calidad de Interacción Familiar (PQIF) para madres, padres y relatives de niños con SPW. En el estudio formaron parte siete participantes asociados a la clínica ambulatoria ICW-HCFMUSP SPW y se aplicaron instrumentos en las fases previa, posterior a la prueba y en la fase de seguimiento. El puntaje del estilo parental demostró un aumento en el uso de prácticas parentales positivas para seis de los siete participantes. Los participantes también mostraron una mejora en la autoobservación, una expansión en el análisis de la conducta y un repertorio de manejo apropiado. Se discuten los límites de este estudio, sin embargo, los datos refuerzan la importancia de validar las herramientas para esta población


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Relações Familiares
20.
Rev Paul Pediatr ; 36(3): 345-352, 2018.
Artigo em Português, Inglês | MEDLINE | ID: mdl-30365815

RESUMO

OBJECTIVE: To carry out a review about Prader-Willi Syndrome based on the most recent data about the subject and to give recommendation for the general pediatricians for early diagnoses and follow-up. DATA SOURCES: Scientific articles in the PubMed and SciELO databases. The research was not limited to a specific time period and included all articles in such databases. DATA SYNTHESIS: The Prader-Willi Syndrome (PWS) is a rare genetic disorder resulting from the loss of imprinted gene expression within the paternal chromosome 15q11-q13. PWS is characterized by endocrine abnormalities, such as growth hormone (GH) deficiency, obesity, central adrenal insufficiency, hypothyroidism, hypogonadism and complex behavioral and intellectual difficulties. PWS individuals also may present other comorbidities, such as sleep disorders, scoliosis, constipation, dental issues and coagulation disorders. The follow-up protocol of the Children's Institute at Universidade de São Paulo is based on four main pillars: diet, exercise, recombinant human growth hormone (rhGH) therapy and behavioral and cognitive issues. The diet must include a caloric restriction of 900 kcal/day, according to the Prader-Willi Eating Pyramid and exercise plan is focused on daily aerobic exercises and postural therapy. The rhGH therapy is highly recommended by the international scientific literature and must be started as soon as the diagnostic is made. The management of behavioral issues is based on strategies to establish routine and rules. CONCLUSIONS: If the general pediatrician becomes more familiar with PWS, the diagnosis and treatment will start earlier, which is essential to improve the quality of life and care for these individuals.


OBJETIVO: Realizar uma revisão sobre a Síndrome de Prader-Willi (SPW) com base nas publicações mais recentes e fornecer recomendações ao pediatra geral para diagnóstico precoce e seguimento. FONTE DE DADOS: Artigos publicados nas bases Pubmed e SciELO. A pesquisa não foi limitada a um período e incluiu todos os artigos das bases de dados. SÍNTESE DOS DADOS: A SPW é uma síndrome genética rara, resultante da perda do imprinting gênico expresso no cromossomo paterno 15q11-q13, sendo caracterizada por alterações endocrinológicas, como deficiência de hormônio de crescimento, obesidade, insuficiência adrenal central, hipotireoidismo, hipogonadismo, além de alterações comportamentais e déficit intelectual. Há outras comorbidades associadas, como distúrbios de sono, escoliose, constipação, problemas dentários e alterações de coagulação. O protocolo de seguimento da SPW do Instituto da Criança da Universidade de São Paulo se baseia em quarto pilares principais: dieta, exercício físico, terapia com hormônio de crescimento humano recombinante (rhGH) e manejo comportamental e cognitivo. A dieta deve ser restrita a 900 kcal/dia, de acordo com a Pirâmide Alimentar do Prader-Willi, e o exercício físico deve ser diário, aeróbico e postural. A terapia com rhGH é fortemente recomendada pela literatura científica internacional e deve ser iniciada assim que for realizado o diagnóstico da síndrome. O manejo do comportamento é realizado com estratégias para estabelecer rotina e regras. CONCLUSÕES: Se a SPW se tornar mais familiar ao pediatra geral, o diagnóstico e o tratamento começarão mais precocemente, o que irá melhorar a qualidade de vida e os cuidados desses pacientes.


Assuntos
Síndrome de Prader-Willi/diagnóstico , Síndrome de Prader-Willi/terapia , Humanos , Pediatria , Guias de Prática Clínica como Assunto
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