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1.
Intern Med ; 59(15): 1811-1817, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32741890

RESUMO

Objective Although most patients who obtain a sustained virological response (SVR) show an improved liver function, some show decreased platelet counts after the eradication of hepatitis C virus (HCV). The aim of this retrospective study was to clarify the association of the liver and spleen volumes with the platelet count after SVR achieved by direct-acting antiviral (DAA) treatment. Methods This study enrolled 36 consecutive patients treated by DAAs who obtained an SVR between September 2014 and December 2018. The liver and spleen volumes were derived from computed tomography scans obtained at pretreatment, SVR, and 48 weeks after SVR. No patient developed hepatocellular carcinoma during this study. Results Compared with pretreatment, the median aspartate aminotransferase, alanine aminotransferase, albumin serum levels, and platelet counts were significantly improved at SVR and 48 weeks after SVR. The liver/spleen volumes per body weight had decreased significantly from 22.5/4.2 mL/kg at baseline to 21.1/3.6 mL/kg at 48 weeks after SVR. The change in the liver volume was associated with the change in the platelet count, and the change in the spleen volume was negatively associated with the change in the serum albumin level. A multivariate analysis identified the change in the liver volume (≥95%, odds ratio 76.9, p=0.005) as the factor associated with improvement in the platelet count at 48 weeks after SVR. The patients with an increased liver volume at 48 weeks after SVR showed an increased platelet count. Conclusion Both the liver and spleen volume decreased significantly after the eradication of HCV. The patients with a re-increased liver volume showed a rapid increase in the platelet count.


Assuntos
Antivirais/uso terapêutico , Hepatite C/tratamento farmacológico , Cirrose Hepática/patologia , Tamanho do Órgão/fisiologia , Contagem de Plaquetas/estatística & dados numéricos , Baço/patologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Hepacivirus , Hepatite C/complicações , Humanos , Cirrose Hepática/etiologia , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resposta Viral Sustentada
2.
Nature ; 584(7821): 415-419, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32641829

RESUMO

Sexual dimorphism arises from genetic differences between male and female cells, and from systemic hormonal differences1-3. How sex hormones affect non-reproductive organs is poorly understood, yet highly relevant to health given the sex-biased incidence of many diseases4. Here we report that steroid signalling in Drosophila from the ovaries to the gut promotes growth of the intestine specifically in mated females, and enhances their reproductive output. The active ovaries of the fly produce the steroid hormone ecdysone, which stimulates the division and expansion of intestinal stem cells in two distinct proliferative phases via the steroid receptors EcR and Usp and their downstream targets Broad, Eip75B and Hr3. Although ecdysone-dependent growth of the female gut augments fecundity, the more active and more numerous intestinal stem cells also increase female susceptibility to age-dependent gut dysplasia and tumorigenesis, thus potentially reducing lifespan. This work highlights the trade-offs in fitness traits that occur when inter-organ signalling alters stem-cell behaviour to optimize organ size.


Assuntos
Drosophila melanogaster/metabolismo , Fertilidade/fisiologia , Intestinos/crescimento & desenvolvimento , Longevidade/fisiologia , Tamanho do Órgão/fisiologia , Ovário/metabolismo , Esteroides/metabolismo , Envelhecimento , Animais , Carcinogênese , Proliferação de Células , Copulação/fisiologia , Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/anatomia & histologia , Drosophila melanogaster/citologia , Drosophila melanogaster/fisiologia , Ecdisona/metabolismo , Feminino , Mucosa Intestinal/anatomia & histologia , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Intestinos/anatomia & histologia , Intestinos/citologia , Intestinos/patologia , Masculino , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores de Esteroides/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Fatores de Transcrição/metabolismo
3.
Heart Fail Clin ; 16(3): 255-269, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32503750

RESUMO

Acute myocardial infarction (AMI) results in significant changes in cardiac structure and functions, leading to left ventricular remodeling and subsequent systolic and diastolic dysfunction. To improve current approaches in diagnoses, treatments, and prevention of cardiovascular diseases, a better understanding of cardiac mechanoenergetics, including systolic performance and energy demand, becomes paramount. In this review, we summarize cardiac mechanics, cardiac energetics, and their relationship in complications related to AMI using 2 important physiologic frameworks, pressure-volume loops and the Vo2-pressure-volume area relationship diagram, as they are powerful tools for understanding physiologic behavior and mechanoenergetics of the left ventricle.


Assuntos
Insuficiência Cardíaca/etiologia , Ventrículos do Coração , Infarto do Miocárdio , Miocárdio/metabolismo , Tamanho do Órgão/fisiologia , Consumo de Oxigênio/fisiologia , Pressão Ventricular/fisiologia , Metabolismo Energético , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Humanos , Modelos Cardiovasculares , Infarto do Miocárdio/complicações , Infarto do Miocárdio/metabolismo
4.
Obesity (Silver Spring) ; 28(7): 1263-1269, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32427420

RESUMO

OBJECTIVE: This study aimed to investigate cross-sectional and longitudinal associations between fat mass (i.e., body mass index [BMI], waist circumference [WC], and waist to hip ratio [WTHR]) and hippocampal volumes. METHODS: UK Biobank participants (N = 20,395) aged 40 to 70 years (mean follow-up = 7.66 years), were included and categorized into one of four groups, which represented their baseline fat mass status and trajectory of change by follow-up assessment: normal weight to overweight/obesity, overweight/obesity to normal weight (ON), normal weight stable (NS), or overweight/obesity stable (OS). Regression models used NS (WC < 80 cm in women and < 94 cm in men; WTHR < 0.85 in women and < 0.90 in men; BMI < 25 kg/m2 in women and men) as the reference group. Hippocampal volumes were automatically segmented using the FMRIB Software Library. RESULTS: Compared with NS, OS (BMI: B = -62.23 [SE = 16.76]; WC: B = -145.56 [SE = 16.97]; WTHR: B = -101.26 [SE = 19.54]) and ON (BMI: B = -61.1 [SE = 30.3]; WC: B = -93.77 [SE = 24.96]; WTHR: B = -69.92 [SE = 26.22]) had significantly lower hippocampal volumes. CONCLUSIONS: The detrimental effects of overweight/obesity may extend beyond the duration of overweight/obesity itself.


Assuntos
Tecido Adiposo/patologia , Adiposidade/fisiologia , Hipocampo/patologia , Tecido Adiposo/metabolismo , Adulto , Idoso , Índice de Massa Corporal , Estudos Transversais , Feminino , Humanos , Peso Corporal Ideal/fisiologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Obesidade/epidemiologia , Obesidade/metabolismo , Obesidade/patologia , Tamanho do Órgão/fisiologia , Sobrepeso/epidemiologia , Sobrepeso/metabolismo , Sobrepeso/patologia , Reino Unido/epidemiologia , Circunferência da Cintura , Relação Cintura-Quadril
5.
Ann Neurol ; 88(1): 170-182, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32379905

RESUMO

OBJECTIVE: Cognitive problems, especially disturbances in episodic memory, and hippocampal sclerosis are common in temporal lobe epilepsy (TLE), but little is known about the relationship of hippocampal morphology with memory. We aimed to relate hippocampal surface-shape patterns to verbal and visual learning. METHODS: We analyzed hippocampal surface shapes on high-resolution magnetic resonance images and the Adult Memory and Information Processing Battery in 145 unilateral refractory TLE patients undergoing epilepsy surgery, a validation set of 55 unilateral refractory TLE patients, and 39 age- and sex-matched healthy volunteers. RESULTS: Both left TLE (LTLE) and right TLE (RTLE) patients had lower verbal (LTLE 44 ± 11; RTLE 45 ± 10) and visual learning (LTLE 34 ± 8, RTLE 30 ± 8) scores than healthy controls (verbal 58 ± 8, visual 39 ± 6; p < 0.001). Verbal learning was more impaired the greater the atrophy of the left superolateral hippocampal head. In contrast, visual memory was worse with greater bilateral inferomedial hippocampal atrophy. Postsurgical verbal memory decline was more common in LTLE than in RTLE (reliable change index in LTLE 27% vs RTLE 7%, p = 0.006), whereas there were no differences in postsurgical visual memory decline between those groups. Preoperative atrophy of the left hippocampal tail predicted postsurgical verbal memory decline. INTERPRETATION: Memory deficits in TLE are associated with specific morphological alterations of the hippocampus, which could help stratify TLE patients into those at high versus low risk of presurgical or postsurgical memory deficits. This knowledge could improve planning and prognosis of selective epilepsy surgery and neuropsychological counseling in TLE. ANN NEUROL 2020 ANN NEUROL 2020;88:170-182.


Assuntos
Epilepsia do Lobo Temporal/diagnóstico por imagem , Hipocampo/diagnóstico por imagem , Transtornos da Memória/diagnóstico por imagem , Memória Episódica , Adulto , Mapeamento Encefálico , Epilepsia do Lobo Temporal/complicações , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Transtornos da Memória/etiologia , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tamanho do Órgão/fisiologia
6.
J Anim Sci ; 98(5)2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32255481

RESUMO

A study was conducted to determine effects of reducing hindgut pH through dietary inclusion of high-amylose cornstarch (HA-starch) on growth performance, organ weights relative to live body weight (BW), blood thyroid hormone levels, and glucosinolate degradation products of nursery pigs fed cold-pressed canola cake (CPCC). A total of 240 pigs (initial BW: 7.1 kg), which had been weaned at 21 d of age, were housed in 40 pens (6 pigs per pen) and fed 4 diets (10 pens per diet) in a randomized complete block design for 28 d. Four diets were a basal diet with CPCC at 0 or 40%, and with HA-starch at 0 or 40% in a 2 × 2 factorial arrangement. The diets were fed in two phases: Phase 1 from day 0 to 14 and Phase 2 from day 14 to 28 and were formulated to have the same net energy, standardized ileal digestible AA, Ca, and standardized total tract digestible P contents. Dietary inclusion of CPCC and HA-starch was achieved by a partial or complete replacement of corn, soybean meal, and soy protein. At the end of the study, one pig from each pen was euthanized to determine organ weights, blood parameters, hindgut pH, and glucosinolate degradation products. Dietary CPCC reduced (P < 0.05) overall average daily gain (ADG) by 15%; increased (P < 0.05) relative weights of liver and thyroid gland by 27% and 64%, respectively; and reduced (P < 0.05) serum tetraiodothyronine (T4) level from 30.3 to 17.8 ng/mL. Heart, kidney, and gastrointestinal tract weights; serum triiodothyronine level; and hindgut pH of pigs were unaffected by dietary CPCC. Dietary HA-starch reduced (P < 0.05) overall ADG, relative weight of thyroid gland, cecal, and colonic pH; but increased (P < 0.05) relative weight of colon; tended to increase (P = 0.062) serum T4 level. Dietary CPCC and HA-starch interacted (P = 0.024) on relative weight of thyroid gland such that dietary CPCC increased (P < 0.05) weight of thyroid gland for HA-starch-free diet (120 vs. 197 mg/kg of BW) but not for HA-starch-containing diet (104 vs. 130 mg/kg of BW). Dietary CPCC and HA-starch interacted (P = 0.001) on cecal isothiocyanate content such that dietary CPCC increased (P < 0.05) level of isothiocyanates for HA-starch-containing diet but not for HA-starch-free diet. In conclusion, dietary CPCC reduced growth performance, increased liver, size and interfered with thyroid gland functions of pigs. However, the negative effects of dietary CPCC on thyroid gland functions of nursery pigs were alleviated by dietary HA-starch.


Assuntos
Ração Animal/análise , Brassica napus/química , Glucosinolatos/toxicidade , Amido/metabolismo , Suínos/fisiologia , Animais , Ceco/efeitos dos fármacos , Ceco/fisiologia , Dieta/veterinária , Feminino , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/fisiologia , Fígado/efeitos dos fármacos , Fígado/fisiologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Tamanho do Órgão/fisiologia , Soja , Zea mays
7.
PLoS One ; 15(3): e0229525, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32134922

RESUMO

Determination of hepatic volume is an important preoperative procedure and is done through imaging exams or standard liver volume (SLV) formulas developed based on the biotype of each population. In the absence of a specific SLV formula for the Brazilian Eastern Amazon population, the measurement of liver volume is made with reference values from other populations. The aim of study was to compare the hepatic volume in healthy residents from the Brazilian Eastern Amazon population obtained with magnetic resonance imaging (MRI) and recommended SLV formulas validated to other populations. This was a Observational, cross-sectional study. Anthropometric data of 42 healthy individuals aged 18-60 years of both sexes was collected to measure the liver volume through SLV formulas calculations and MRI. MRI shows similarity with the Western European SLV liver volume values and significant differences with the Japan SLV formula, mainly for women, with a moderate-to-weak correlation with the MRI measurements. There was a strong correlation between weight and body surface area in male patients analysed with measurements of the liver volume by the MRI and SLV formulas. The SLV formula based on the Western European population could be used in the absence of a specific formula for individuals living in the Amazon region. The results suggest that liver measurement formulas should take into consideration the sex of individuals, as well as the development of a specific SLV formula for the Eastern Amazon population and the conduction of similar studies in other Brazilian regions.


Assuntos
Fígado/fisiologia , Adolescente , Adulto , Superfície Corporal , Peso Corporal/fisiologia , Brasil , Estudos Transversais , Feminino , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão/fisiologia , Adulto Jovem
8.
Transplantation ; 104(6): e174-e181, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32044891

RESUMO

BACKGROUND: Despite the routine use of hemodynamic assessment in pediatric heart transplant (HT) patients, expected intracardiac pressure measurements in patients free of significant complications are incompletely described. A better understanding of the range of intracardiac pressures in these HT patients is important for the clinical interpretation of these indices and consequent management of patients. METHODS: We conducted a retrospective chart review of pediatric HT recipients who had undergone HT between January 2010 and December 2015 at Lucile Packard Children's Hospital. We analyzed intracardiac pressures measured in the first 12 mo after HT. We excluded those with rejection, graft coronary artery disease, mechanical support, or hemodialysis. We used a longitudinal general additive model with bootstrapping technique to generate age and donor-recipient size-specific curves to characterize filling pressures through 1-y post-HT. RESULTS: Pressure measurements from the right atrium, pulmonary artery, and pulmonary capillary wedge pressure were obtained in 85 patients during a total of 829 catheterizations. All pressure measurements were elevated in the immediate post-HT period and decreased to a stable level by post-HT day 90. Pressure measurements were not affected by age group, donor-recipient size differences, or ischemic time. CONCLUSIONS: Intracardiac pressures are elevated in the early post-HT period and decrease to levels typical of the native heart by 90 d. Age, donor-to-recipient size differences, and ischemic time do not contribute to differences in expected intracardiac pressures in the first year post-HT.


Assuntos
Aloenxertos/fisiologia , Transplante de Coração , Coração/fisiologia , Modelos Cardiovasculares , Pressão Ventricular/fisiologia , Adolescente , Fatores Etários , Aloenxertos/anatomia & histologia , Aloenxertos/estatística & dados numéricos , Criança , Pré-Escolar , Isquemia Fria/estatística & dados numéricos , Feminino , Coração/anatomia & histologia , Humanos , Lactente , Masculino , Tamanho do Órgão/fisiologia , Período Pós-Operatório , Estudos Retrospectivos , Doadores de Tecidos/estatística & dados numéricos , Transplantados/estatística & dados numéricos , Transplante Homólogo , Isquemia Quente/estatística & dados numéricos
9.
Acta Cir Bras ; 34(11): e201901103, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31939502

RESUMO

PURPOSE: To evaluate liver regeneration after selective ligation of portal vein and hepatic artery by 3D Computed Tomography in an experimental model. METHODS: Sixteen Wistar rats were randomized into four equal groups: Group I- control (sham), Group II- isolated selective ligation of the hepatic artery, Group III- isolated selective ligation of the portal vein and Group IV- combined ligation of portal vein and hepatic artery. Before procedure and five days after a 3D CT Scan was performed to analyze the hypertrophy, weight and function of the remnant liver. RESULTS: The largest regeneration rate and increase of weight in the hypertrophied lobe was detected in group IV, the first with an average of 3.99 (p=0.006) and the last varying from 6.10g to 9.64g (p=0.01). However, total liver weight and the R1 ratio (Hypertrophied Lobe Weight/Total Liver Weight) was higher in group III (P<0.001) when compared with groups I, II and IV and showed no difference between them. The immunohistochemical examination with PCNA also found higher percentages with statistical significance differences in rats of groups III and IV. It was possible to confirm a strong correlation between hypertrophied lobe weight and its imaging volumetric study. Liver function tests only showed a significant difference in serum gamma-glutamyltransferase and phosphorous. CONCLUSION: There is a largest liver regeneration after combined ligation of portal vein and hepatic artery and this evidence may improve the knowledge of surgical treatment of liver injuries, with a translational impact in anima nobile.


Assuntos
Artéria Hepática/cirurgia , Regeneração Hepática/fisiologia , Fígado/diagnóstico por imagem , Veia Porta/cirurgia , Animais , Hepatomegalia/diagnóstico por imagem , Hepatomegalia/fisiopatologia , Imageamento Tridimensional/métodos , Imuno-Histoquímica , Ligadura , Fígado/irrigação sanguínea , Fígado/patologia , Masculino , Tamanho do Órgão/fisiologia , Distribuição Aleatória , Ratos Wistar , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
10.
JAMA Neurol ; 77(4): 451-460, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31904767

RESUMO

Importance: Identifying risk factors for brain atrophy during the aging process can help direct new preventive approaches for dementia and cognitive decline. The association of neighborhood socioeconomic disadvantage with brain volume in this context is not well known. Objective: To test whether neighborhood-level socioeconomic disadvantage is associated with decreased brain volume in a cognitively unimpaired population enriched for Alzheimer disease risk. Design, Setting, and Participants: This study, conducted from January 6, 2010, to January 17, 2019, at an academic research neuroimaging center, used cross-sectional data on 951 participants from 2 large, ongoing cohort studies of Alzheimer disease (Wisconsin Registry for Alzheimer's Prevention and Wisconsin Alzheimer's Disease Research Center clinical cohort). Participants were cognitively unimpaired based on National Institute on Aging-Alzheimer's Association workgroup diagnostic criteria for mild cognitive impairment and Alzheimer disease, confirmed through a consensus diagnosis panel. The cohort was enriched for Alzheimer disease risk based on family history of dementia. Statistical analysis was performed from April 3 to September 27, 2019. Main Outcomes and Measures: The Area Deprivation Index, a geospatially determined index of neighborhood-level disadvantage, and cardiovascular disease risk indices were calculated for each participant. Linear regression models were fitted to test associations between relative neighborhood-level disadvantage (highest 20% based on state of residence) and hippocampal and total brain tissue volume, as assessed by magnetic resonance imaging. Results: In the primary analysis of 951 participants (637 women [67.0%]; mean [SD] age, 63.9 [8.1] years), living in the 20% most disadvantaged neighborhoods was associated with 4.1% lower hippocampal volume (ß = -317.44; 95% CI, -543.32 to -91.56; P = .006) and 2.0% lower total brain tissue volume (ß = -20 959.67; 95% CI, -37 611.92 to -4307.43; P = .01), after controlling for intracranial volume, individual-level educational attainment, age, and sex. Robust propensity score-matched analyses determined that this association was not due to racial/ethnic or demographic characteristics. Cardiovascular risk score, examined in a subsample of 893 participants, mediated this association for total brain tissue but not for hippocampal volume. Conclusions and Relevance: For cognitively unimpaired individuals, living in the most disadvantaged neighborhoods was associated with significantly lower cerebral volumes, after controlling for maximal premorbid (total intracranial) volume. This finding suggests an association of community socioeconomic context, distinct from individual-level socioeconomic status, with brain volume during aging. Cardiovascular risk mediated this association for total brain tissue volume but not for hippocampal volume, suggesting that neighborhood-level disadvantage may be associated with these 2 outcomes via distinct biological pathways.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Hipocampo/diagnóstico por imagem , Pobreza , Idoso , Estudos Transversais , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neuroimagem , Tamanho do Órgão/fisiologia , Fatores de Risco , Fatores Socioeconômicos
11.
Toxicol Lett ; 319: 95-101, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31678400

RESUMO

Physiologically based kinetic (PBK) models for farm animals are of growing interest in food and feed safety with key applications for regulated compounds including quantification of tissue concentrations, kinetic parameters and the setting of safe exposure levels on an internal dose basis. The development and application of these models requires data for physiological, anatomical and chemical specific parameters. Here, we present the results of a structured data collection of anatomical and physiological parameters in three key farm animal species (swine, cattle and sheep). We performed an extensive literature search and meta-analyses to quantify intra-species variability and associated uncertainty of the parameters. Parameters were collected for organ weights and blood flows in all available breeds from 110 scientific publications, of which 29, 48 and 33 for cattle, sheep, and swine, respectively. Organ weights were available in literature for all three species. Blood flow parameter values were available for all organs in sheep but were scarcer in swine and cattle. Furthermore, the parameter values showed a large intra-species variation. Overall, the parameter values and associated variability provide reference values which can be used as input for generic PBK models in these species.


Assuntos
Animais Domésticos/metabolismo , Bovinos/metabolismo , Farmacocinética , Carneiro Doméstico/metabolismo , Suínos/metabolismo , Animais , Peso Corporal/fisiologia , Bovinos/anatomia & histologia , Modelos Biológicos , Tamanho do Órgão/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Carneiro Doméstico/anatomia & histologia , Especificidade da Espécie , Suínos/anatomia & histologia
12.
Proc Natl Acad Sci U S A ; 117(1): 472-478, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31871184

RESUMO

The unique engulfment filtration strategy of microphagous rorqual whales has evolved relatively recently (<5 Ma) and exploits extreme predator/prey size ratios to overcome the maneuverability advantages of swarms of small prey, such as krill. Forage fish, in contrast, have been engaged in evolutionary arms races with their predators for more than 100 million years and have performance capabilities that suggest they should easily evade whale-sized predators, yet they are regularly hunted by some species of rorqual whales. To explore this phenomenon, we determined, in a laboratory setting, when individual anchovies initiated escape from virtually approaching whales, then used these results along with in situ humpback whale attack data to model how predator speed and engulfment timing affected capture rates. Anchovies were found to respond to approaching visual looming stimuli at expansion rates that give ample chance to escape from a sea lion-sized predator, but humpback whales could capture as much as 30-60% of a school at once because the increase in their apparent (visual) size does not cross their prey's response threshold until after rapid jaw expansion. Humpback whales are, thus, incentivized to delay engulfment until they are very close to a prey school, even if this results in higher hydrodynamic drag. This potential exaptation of a microphagous filter feeding strategy for fish foraging enables humpback whales to achieve 7× the energetic efficiency (per lunge) of krill foraging, allowing for flexible foraging strategies that may underlie their ecological success in fluctuating oceanic conditions.


Assuntos
Reação de Fuga/fisiologia , Comportamento Alimentar , Peixes/fisiologia , Jubarte/fisiologia , Comportamento Predatório/fisiologia , Animais , Evolução Biológica , Euphausiacea/fisiologia , Filtração , Jubarte/anatomia & histologia , Hidrodinâmica , Arcada Osseodentária/anatomia & histologia , Locomoção/fisiologia , Modelos Biológicos , Tamanho do Órgão/fisiologia , Fatores de Tempo
13.
PLoS One ; 14(12): e0226525, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31869402

RESUMO

BACKGROUND: Grey matter volume (GMV) decline is a frequent finding in multiple sclerosis (MS), the most common chronic neurological disease in young adults. Increases of GMV were detected in language related brain regions following second language (L2) learning in healthy adults. Effects of L2 learning in people with MS (pwMS) have not been investigated so far. METHODS: This study prospectively evaluated the potential of an eight-week L2 training on grey matter plasticity measured by 3T-MRI, L2 proficiency and health-related quality of life (HRQoL) in people with relapsing-remitting MS (pwMS, n = 11) and healthy, sex- and age-matched controls (HCs; n = 12). RESULTS: Categorical voxel-based analysis revealed significantly less GMV bilaterally of the insula extending to the temporal pole in pwMS at baseline. Following L2 training, significant increases of GMV were evident in the right hippocampus, parahippocampus and putamen of pwMS and in the left insula of HCs. L2 training resulted in significant improvements of listening comprehension, speaking fluency and vocabulary knowledge in both pwMS and HCs. GMV increases of right hippocampus and parahippocampus significantly correlated with vocabulary knowledge gain and L2 learning was associated with a significant increase of HRQoL in pwMS. CONCLUSION: Our findings demonstrate distinct patterns of GMV increases of language related brain regions in pwMS and HCs and indicate disease-related compensatory cortical and subcortical plasticity to acquire L2 proficiency in pwMS.


Assuntos
Substância Cinzenta/crescimento & desenvolvimento , Substância Cinzenta/patologia , Idioma , Aprendizagem , Multilinguismo , Esclerose Múltipla/patologia , Adulto , Mapeamento Encefálico , Compreensão/fisiologia , Feminino , Substância Cinzenta/diagnóstico por imagem , Humanos , Estudos Longitudinais , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/psicologia , Tamanho do Órgão/fisiologia , Qualidade de Vida , Vocabulário
14.
Development ; 146(24)2019 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-31862792

RESUMO

In order to contribute to the appropriate tissues during development, cells need to know their position within the embryo. This positional information is conveyed by gradients of signaling molecules, termed morphogens, that are produced in specific regions of the embryo and induce concentration-dependent responses in target tissues. Positional information is remarkably robust, and embryos often develop with the correct proportions even if large parts of the embryo are removed. In this Review, we discuss classical embryological experiments and modern quantitative analyses that have led to mechanistic insights into how morphogen gradients adapt, scale and properly pattern differently sized domains. We analyze these experimental findings in the context of mathematical models and synthesize general principles that apply to multiple systems across species and developmental stages.


Assuntos
Padronização Corporal/fisiologia , Tamanho Corporal/fisiologia , Morfogênese/fisiologia , Tamanho do Órgão/fisiologia , Regeneração/fisiologia , Animais , Movimento Celular/fisiologia , Polaridade Celular/fisiologia , Humanos , Modelos Teóricos
15.
Alzheimers Res Ther ; 11(1): 109, 2019 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-31878968

RESUMO

BACKGROUND: We examined interactive effects of sex, diagnosis, and cerebrospinal fluid (CSF) amyloid beta/phosphorylated tau ratio (Aß/P-tau) on verbal memory and hippocampal volumes. METHODS: We assessed 682 participants (350 women) from BioFINDER (250 cognitively normal [CN]; and 432 symptomatic: 186 subjective cognitive decline [SCD], 246 mild cognitive impairment [MCI]). General linear models evaluated effects of Alzheimer's disease (AD) proteinopathy (CSF Aß/p-tau ratio), diagnosis, and sex on verbal memory (ADAS-cog 10-word recall), semantic fluency (animal naming fluency), visuospatial skills (cube copy), processing speed/attention functions (Symbol Digit Modalities Test and Trail Making Part A), and hippocampal volumes. RESULTS: Amyloid-positive (Aß/P-tau+) CN women (women with preclinical AD) showed memory equivalent to amyloid-negative (Aß/P-tau-) CN women. In contrast, Aß/P-tau+ CN men (men with preclinical AD) showed poorer memory than Aß/P-tau- CN men. Symptomatic groups showed no sex differences in effect of AD proteinopathy on memory. There was no interactive effect of sex, diagnosis, and Aß/P-tau on other measures of cognition or on hippocampal volume. CONCLUSIONS: CN women show relatively preserved verbal memory, but not general cognitive reserve or preserved hippocampal volume in the presence of Aß/P-tau+. Results have implications for diagnosing AD in women, and for clinical trials.


Assuntos
Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Cognição/fisiologia , Hipocampo/patologia , Memória/fisiologia , Idoso , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/psicologia , Feminino , Hipocampo/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tamanho do Órgão/fisiologia , Fragmentos de Peptídeos/líquido cefalorraquidiano , Fosforilação , Caracteres Sexuais , Proteínas tau/líquido cefalorraquidiano
16.
Int J Comput Assist Radiol Surg ; 14(12): 2083-2093, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31705418

RESUMO

PURPOSE: Liver shape variations have been considered as feasible indicators of liver fibrosis. However, current statistical shape models (SSM) based on principal component analysis represent gross shape variations without considering the association with the fibrosis stage. Therefore, we aimed at the application of a statistical shape modelling approach using partial least squares regression (PLSR), which explicitly uses the stage as supervised information, for understanding the shape variations associated with the stage as well as predicting it in contrast-enhanced MR images. METHODS: Contrast-enhanced MR images of 51 patients with fibrosis stages F0/1 (n = 18), F2 (n = 15), F3 (n = 7) and F4 (n = 11) were used. The livers were manually segmented from the images. An SSM was constructed using PLSR, by which shape variation modes (scores) that were explicitly associated with the reference pathological fibrosis stage were derived. The stage was predicted using a support vector machine (SVM) based on the PLSR scores. The performance was assessed using the area under receiver operating characteristic curve (AUC). RESULTS: In addition to commonly known shape variations, such as enlargement of left lobe and shrinkage of right lobe, our model represented detailed variations, such as enlargement of caudate lobe and the posterior part of right lobe, and shrinkage in the anterior part of right lobe. These variations qualitatively agreed with localized volumetric variations reported in clinical studies. The accuracy (AUC) at classifications F0/1 versus F2‒4 (significant fibrosis), F0‒2 versus F3‒4 and F0‒3 versus F4 (cirrhosis) were 0.90 ± 0.03, 0.80 ± 0.05 and 0.82 ± 0.05, respectively. CONCLUSIONS: The proposed approach offered an explicit representation of commonly known as well as detailed shape variations associated with liver fibrosis stage. Thus, the application of PLSR-based SSM is feasible for understanding the shape variations associated with the liver fibrosis stage and predicting it.


Assuntos
Aumento da Imagem/métodos , Cirrose Hepática/diagnóstico por imagem , Fígado/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Análise dos Mínimos Quadrados , Fígado/patologia , Cirrose Hepática/patologia , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Tamanho do Órgão/fisiologia , Máquina de Vetores de Suporte
17.
Acta cir. bras ; 34(11): e201901103, Nov. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1054680

RESUMO

Abstract Purpose: To evaluate liver regeneration after selective ligation of portal vein and hepatic artery by 3D Computed Tomography in an experimental model. Methods: Sixteen Wistar rats were randomized into four equal groups: Group I- control (sham), Group II- isolated selective ligation of the hepatic artery, Group III- isolated selective ligation of the portal vein and Group IV- combined ligation of portal vein and hepatic artery. Before procedure and five days after a 3D CT Scan was performed to analyze the hypertrophy, weight and function of the remnant liver. Results: The largest regeneration rate and increase of weight in the hypertrophied lobe was detected in group IV, the first with an average of 3.99 (p=0.006) and the last varying from 6.10g to 9.64g (p=0.01). However, total liver weight and the R1 ratio (Hypertrophied Lobe Weight/Total Liver Weight) was higher in group III (P<0.001) when compared with groups I, II and IV and showed no difference between them. The immunohistochemical examination with PCNA also found higher percentages with statistical significance differences in rats of groups III and IV. It was possible to confirm a strong correlation between hypertrophied lobe weight and its imaging volumetric study. Liver function tests only showed a significant difference in serum gamma-glutamyltransferase and phosphorous. Conclusion: There is a largest liver regeneration after combined ligation of portal vein and hepatic artery and this evidence may improve the knowledge of surgical treatment of liver injuries, with a translational impact in anima nobile.


Assuntos
Animais , Masculino , Veia Porta/cirurgia , Artéria Hepática/cirurgia , Fígado/diagnóstico por imagem , Regeneração Hepática/fisiologia , Tamanho do Órgão/fisiologia , Imuno-Histoquímica , Distribuição Aleatória , Tomografia Computadorizada por Raios X/métodos , Reprodutibilidade dos Testes , Resultado do Tratamento , Ratos Wistar , Imageamento Tridimensional/métodos , Hepatomegalia/fisiopatologia , Hepatomegalia/diagnóstico por imagem , Ligadura , Fígado/irrigação sanguínea , Fígado/patologia
18.
Int J Dev Neurosci ; 79: 11-20, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31563705

RESUMO

INTRODUCTION: Little is known regarding the impact of concurrent critical illness and thoracic noncardiac perioperative critical care on postnatal brain development. Previously, we reported smaller total brain volumes in both critically ill full-term and premature patients following complex perioperative critical care for long-gap esophageal atresia (LGEA). Our current report assessed trends in regional brain sizes during infancy, and probed for any group differences. METHODS: Full-term (n = 13) and preterm (n = 13) patients without any previously known neurological concerns, and control infants (n = 16), underwent non-sedated 3 T MRI in infancy (<1 year old). T2-weighted images underwent semi-automated brain segmentation using Morphologically Adaptive Neonatal Tissue Segmentation (MANTiS). Regional tissue volumes of the forebrain, deep gray matter (DGM), cerebellum, and brainstem are presented as absolute (cm3) and normalized (% total brain volume (%TBV)) values. Group differences were assessed using a general linear model univariate analysis with corrected age at scan as a covariate. RESULTS: Absolute volumes of regions analyzed increased with advancing age, paralleling total brain size, but were significantly smaller in both full-term and premature patients compared to controls. Normalized volumes (%TBV) of forebrain, DGM, and cerebellum were not different between subject groups analyzed. Normalized brainstem volumes showed group differences that warrant future studies to confirm the same finding. DISCUSSION: Both full-term and premature critically ill infants undergoing life-saving surgery for LGEA are at risk of smaller total and regional brain sizes. Normalized volumes support globally delayed or diminished brain growth in patients. Future research should look into neurodevelopmental outcomes of infants born with LGEA.


Assuntos
Encéfalo/diagnóstico por imagem , Atresia Esofágica/cirurgia , Encéfalo/crescimento & desenvolvimento , Cuidados Críticos , Atresia Esofágica/diagnóstico por imagem , Feminino , Humanos , Lactente , Recém-Nascido Prematuro , Imagem por Ressonância Magnética , Masculino , Tamanho do Órgão/fisiologia , Projetos Piloto , Período Pós-Operatório
19.
Can J Physiol Pharmacol ; 97(12): 1185-1192, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31505126

RESUMO

Several studies have reported that high doses of synthetic anabolic androgenic steroids (AAS) can have serious negative effects on health, including the cardiovascular system. The aim of this study was to evaluate the combined effects of AAS and exercise training on ventricular repolarization and cardiac autonomic modulation in rats. Male Wistar rats were allocated into 4 groups: sedentary rats treated with vehicle, sedentary rats treated with nandrolone decanoate, swimming-trained rats treated with vehicle, and swimming-trained rats treated with nandrolone decanoate. Ventricular repolarization was evaluated by electrocardiographic analysis of QT interval and QT dispersion. Cardiac autonomic modulation was assessed by heart rate variability. Our results show that AAS increased QT interval and QT dispersion in sedentary rats treated with nandrolone decanoate as compared to sedentary rats treated with vehicle, indicating AAS-induced ventricular repolarization abnormalities. When rats treated with nandrolone decanoate were subjected to concomitant exercise training, ventricular repolarization was normalized. On the other hand, AAS-induced reduction in cardiac parasympathetic modulation was not prevented by exercise training. In conclusion, AAS produced cardiac autonomic dysfunction and ventricular repolarization disturbances in rats. Combining an exercise training protocol during the AAS treatment attenuated the ventricular repolarization abnormalities and did not prevent cardiac autonomic dysfunction.


Assuntos
Sistema Nervoso Autônomo/efeitos dos fármacos , Sistema Nervoso Autônomo/fisiologia , Ventrículos do Coração/efeitos dos fármacos , Coração/inervação , Condicionamento Físico Animal , Congêneres da Testosterona/farmacologia , Tecido Adiposo/citologia , Tecido Adiposo/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Relação Dose-Resposta a Droga , Eletrocardiografia/efeitos dos fármacos , Coração/efeitos dos fármacos , Coração/fisiologia , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Tamanho do Órgão/fisiologia , Ratos , Ratos Wistar , Função Ventricular/efeitos dos fármacos
20.
Psychiatry Res Neuroimaging ; 292: 47-53, 2019 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-31521943

RESUMO

The entorhinal cortex (ERC) acts as a connection between the hippocampus and temporal cortex and plays a key role in memory retrieval and navigation. The morphology of this brain region changes with age. However, there are few quantitative magnetic resonance imaging studies of ERC morphology across the healthy adult lifespan. In this study, we quantified ERC volume, thickness, surface area, and curvature in a large number of subjects spanning seven decades of life. Using structural MRI data from 563 healthy subjects ranging from 19 to 86 years of age, we explored the adult lifespan trajectory of ERC volume, thickness, surface and curvature. ERC volume, thickness, and surface area initially increased with age, reaching a peak at about 32 years, 40 years, and 50 years of age, respectively, after which they decreased with age. ERC volume and surface area were hemispherically leftward asymmetric, whereas ERC thickness was hemispherically rightward asymmetric, with no gender differences. The direction of asymmetry differed across the measures. This informs previous inconsistencies in reports of ERC asymmetry. ERC aging began in mid-adulthood. At this stage of life, it may be important to adopt some strategies to reduce the effects of aging on cognition.


Assuntos
Córtex Entorrinal/diagnóstico por imagem , Córtex Entorrinal/fisiologia , Longevidade/fisiologia , Imagem por Ressonância Magnética/tendências , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Bases de Dados Factuais/tendências , Feminino , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão/fisiologia , Adulto Jovem
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