14 results on '"da Silva Souza G"'
Search Results
2. Smartphone-based inertial measurements during Chester step test as a predictor of length of hospital stay in abdominopelvic cancer postoperative period: a prospective cohort study.
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Nascimento AQ, Nagata LAR, Almeida MT, da Silva Costa VL, de Marin ABR, Tavares VB, Ishak G, Callegari B, Santos EGR, da Silva Souza G, and de Melo Neto JS
- Subjects
- Humans, Length of Stay, Prospective Studies, Smartphone, Multivariate Analysis, Exercise Test methods, Neoplasms
- Abstract
Background: Objective assessment of pre-operative functional capacity in cancer patients using the smartphone gyroscope during the Chester step (CST) test may allow greater sensitivity of test results. This study has investigated whether the CST is a postoperative hospital permanence predictor in cancer patients undergoing abdominopelvic surgery through work, VO2MAX and gyroscopic movement analysis., Methods: Prospective, quantitative, descriptive and inferential observational cohort study. Fifty-one patients were evaluated using CST in conjunction with a smartphone gyroscope. Multivariate linear regression analysis was used to examine the predictive value of the CST., Results: The duration of hospital permanence 30 days after surgery was longer when patients who performed stage 1 showed lower RMS amplitude and higher peak power. The work increased as the test progressed in stage 3. High VO2MAX seemed to be a predictor of hospital permanence in those who completed levels 3 and 4 of the test., Conclusion: The use of the gyroscope was more accurate in detecting mobility changes, which predicted a less favorable result for those who met at level 1 of the CST. VO2MAX was a predictor of prolonged hospitalization from level 3 of the test. The work was less accurate to determine the patient's true functional capacity., (© 2024. The Author(s).)
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- 2024
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3. Sexual Function, Physical Activity, Mean Amplitudes and Maximal Voluntary Contraction of Pelvic Floor Muscles Are Related to Handgrip Strength: A Cross-Sectional Study.
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Duarte NS, Bittencourt KC, Soares CO, Ferreira CRG, Soares WM, Tavares VB, da Silva ASA, da Costa Priante CH, das Neves PFM, da Silva Souza G, de Campos Gomes F, Carneiro Nunes EF, Rodrigues CNC, and de Melo Neto JS
- Abstract
Pelvic floor musculature assessment methods are generally invasive, subjective, and technologically expensive. Therefore, there is a need to identify other methods that can predict changes in the function of these muscles. This study aimed to verify whether the levels of strength and myoelectric activity of pelvic floor muscles (PFM) can be related to handgrip strength (HGS), to ensure faster and earlier identification of possible dysfunctions of this musculature. Furthermore, we verified whether these variables vary across different age groups. This was a cross-sectional observational study involving 44 healthy women. The women were divided into two groups: the young (18−35 years) and middle-aged (36−55 years) adult groups. Social, anthropometric, and clinical data were collected from the participants, and a functional assessment of their PFM was performed by bidigital palpation, electromyographic biofeedback (sEMG), and HGS (using a dynamometer). The levels of physical and sexual activity were measured using the International Physical Activity Questionnaire (IPAQ) and Sexual Quotient−Female version (SQ-F) questionnaire. There were no differences in HGS, power/pressure, sEMG, SQ-F score, or IPAQ score between the two groups (p > 0.05). Moderate correlation (r = 0.601; p = 0.019) was observed during multivariate analysis. HGS is related to mean amplitudes (p = 0.123), MVC (p = 0.043), sexual function (p = 0.049), and physical activity (p = 0.004). We therefore conclude that there were no differences between HGS and PFM strength in young adult and middle-aged women. Furthermore, HGS is related to the PFM functionality, sexual function, and physical activity.
- Published
- 2022
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4. Anticipatory postural adjustments in older versus young adults: a systematic review and meta-analysis.
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Duarte MB, da Silva Almeida GC, Costa KHA, Garcez DR, de Athayde Costa E Silva A, da Silva Souza G, de Melo-Neto JS, and Callegari B
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- Humans, Young Adult, Aged, Electromyography, Muscle, Skeletal physiology, Biomechanical Phenomena, Postural Balance physiology, Movement physiology
- Abstract
Background: Anticipatory postural adjustments (APAs) are a feedforward mechanism triggered in advance to a predictable perturbation, to help the individual counteract mechanical effects that the disturbance may cause. Whether or not this strategy is compromised in the elderly is not a consensus in the literature., Methods: In this systematic review with meta-analysis, we investigated aging effects on postural control, based on anticipatory postural adjustments (APAs). We selected 11 eligible articles of the following databases: Lilacs, SciELO, PubMed, Cochrane Central, Embase, and CINAHL, involving 324 research participants, assessing their methodological quality and extracting electromyographic, posturographic, and kinematic measurements. We included studies that investigated the occurrence of APAs in healthy younger and older adults, published before 10th August 2022, in English. Studies involving participant with conditions that may affect balance or that did not report measures of onset or amplitude of electromyography (EMG), COP, or kinematics were excluded. To analyze the aggregated results from these studies, we performed the analysis based on the outcome measures (EMG, COP, or kinematic measures) used in individual studies. We calculated differences between younger and older adult groups as the mean differences between the groups and the estimated effect. Egger's test was conducted to evaluate whether this meta-analysis had publication bias., Results: Through this review, older adults showed no significant difference in the velocity to perform a movement compared to the younger adults (MD 0.95, 95% CI -0.86, 2.76, I
2 = 82%), but both muscle onset and center of pressure (COP) onset were significantly more delayed in older than in younger adults: erector spinae (MD -31.44, 95% CI -61.79, -1.09, I2 = 95%); rectus abdominis (RA) (MD -31.51, 95% CI -70.58, -3.57, I2 = 85%); tibialis anterior (TA) (MD -44.70, 95% CI -94.30, 4.91, I2 = 63%); soleus (SOL) (MD -37.74, 95% CI -65.43, -10.05, I2 = 91%); gastrocnemius (GAS) (MD -120.59, 95% CI -206.70, -34.49, I2 = 94%); quadriceps (Q) (MD -17.42, 95% CI -34.73, -0.12, I2 = 0%); biceps femoris (BF) (MD -117.47, 95% CI -192.55, -42.70, I2 = 97%); COP onset (MD -45.28, 95% CI -89.57, -0.98, I2 = 93%), and COP apa (COPapa) (MD 2.35, 95% CI -0.09, 4.79, I2 = 64%). These changes did not seem to be linked to the speed of movement but possibly to age-related physiological changes that indicated decreased motor control during APAs in older adults., Conclusions: Older adults use different postural strategies that aim to increase the safety margin and stabilize the body to perform the movement, according to the requirements imposed, and this should be considered in rehabilitation protocols., Systematic Review Registration: PROSPERO CRD420119143198., (© 2022. The Author(s).)- Published
- 2022
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5. Wearable Inertial Sensor Approach for Postural Adjustment Assessments during Predictable Perturbations in Sport.
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Duarte MB, da Costa Moraes AA, Ferreira EV, da Silva Almeida GC, Cabral ADS, de Athayde Costa E Silva A, Garcez DR, da Silva Souza G, and Callegari B
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- Humans, Reproducibility of Results, Cross-Sectional Studies, Posture, Postural Balance, Wearable Electronic Devices
- Abstract
Introduction: Evidence supports the importance of efficient postural control to improve performance in sports. This involves the use of strategies such as anticipatory posture adjustments and compensatory adjustments. Technology makes analysis and assessments in sports cheaper, while being valid and reliable compared to the gold-standard assessment equipment., Objectives: This article aimed to test the validity and reliability of signals extracted from the sensor's accelerometer ( Metamotion C ), by comparing it to the data obtained from the gold-standard equipment (a three-dimensional video-motion-capture system)., Design: Observational, cross-sectional study., Methods: We exposed 20 healthy young standing people to the pendulum impact paradigm, which consisted of predictable anteroposterior disturbances applied at the shoulder level. In order to measure this, we observed the acceleration of the center of mass in the anticipatory and compensatory phase of the disturbance and compared the signals of the two devices ( Metamotion C and a motion-capture system)., Results: The validation results showed the significant linear correlation of all variables with a moderate to large correlation of r ≥ 0.5 between the devices. In contrast, the reliability results between sessions obtained by filming were all significant and above 0.75, indicating excellent reliability. The APAonset variable had a reasonable to high intra-class correlation in the anticipatory phase. In the compensatory phase, the CPA
time variable showed an excellent correlation., Conclusions: Metamotion C proved reasonably valid and highly reliable in measuring the center of mass acceleration compared to the camera system in both the anticipatory and compensatory phases.- Published
- 2022
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6. Author Correction: Postural adjustments impairments in elderly people with chronic low back pain.
- Author
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Garcez DR, da Silva Almeida GC, Silva CFO, de Souza Nascimento T, de Athayde Costa E Silva A, Kleiner AFR, da Silva Souza G, Yamada ES, and Callegari B
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- 2021
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7. Uniform trichromacy in Alouatta caraya and Alouatta seniculus: behavioural and genetic colour vision evaluation.
- Author
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Henriques LD, Hauzman E, Bonci DMO, Chang BSW, Muniz JAPC, da Silva Souza G, de Lima Silveira LC, de Faria Galvão O, Goulart PRK, and Ventura DF
- Abstract
Primate colour vision depends on a matrix of photoreceptors, a neuronal post receptoral structure and a combination of genes that culminate in different sensitivity through the visual spectrum. Along with a common cone opsin gene for short wavelengths (sws1), Neotropical primates (Platyrrhini) have only one cone opsin gene for medium-long wavelengths (mws/lws) per X chromosome while Paleotropical primates (Catarrhini), including humans, have two active genes. Therefore, while female platyrrhines may be trichromats, males are always dichromats. The genus Alouatta is inferred to be an exception to this rule, as electrophysiological, behavioural and molecular analyses indicated a potential for male trichromacy in this genus. However, it is very important to ascertain by a combination of genetic and behavioural analyses whether this potential translates in terms of colour discrimination capability. We evaluated two howler monkeys (Alouatta spp.), one male A. caraya and one female A. seniculus, using a combination of genetic analysis of the opsin gene sequences and a behavioral colour discrimination test not previously used in this genus. Both individuals completed the behavioural test with performances typical of trichromatic colour vision and the genetic analysis of the sws1, mws, and lws opsin genes revealed three different opsin sequences in both subjects. These results are consistent with uniform trichromacy in both male and female, with presumed spectral sensitivity peaks similar to Catarrhini, at ~ 430 nm, 532 nm, and 563 nm for S-, M- and L-cones, respectively.
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- 2021
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8. Postural adjustments impairments in elderly people with chronic low back pain.
- Author
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Garcez DR, da Silva Almeida GC, Silva CFO, de Souza Nascimento T, de Athayde Costa E Silva A, Kleiner AFR, da Silva Souza G, Yamada ES, and Callegari B
- Subjects
- Aged, Aging, Chronic Disease, Cross-Sectional Studies, Female, Humans, Male, Posture, Low Back Pain physiopathology, Postural Balance
- Abstract
Chronic low back pain (CLBP) is associated with postural control impairments and is highly prevalent in elderly people. The objective of this study is to verify whether anticipatory postural adjustments (APAs) and compensatory postural adjustments (CPAs) are affected by CLBP in elderly people by assessing their postural control during a self-initiated perturbation paradigm induced by rapid upper arm movement when pointing to a target. The participants' lower limb muscle onset and center of pressure (COP) displacements were assessed prior to perturbation and throughout the entire movement. T
0 moment (i.e., the beginning of the movement) was defined as the anterior deltoid (DEL) onset, and all parameters were calculated with respect to it. The rectus femoris (RT), semitendinosus (ST), and soleous (SOL) showed delayed onset in the CLBP group compared with the control group: RF (control: - 0.094 ± 0.017 s; CLBP: - 0.026 ± 0.012 s, t = 12, p < 0.0001); ST (control: - 0.093 ± 0.013 s; CLBP: - 0.018 ± 0.019 s, t = 12, p < 0.0001); and SOL (control: - 0.086 ± 0.018 s; CLBP: - 0.029 ± 0.015 s, t = 8.98, p < 0.0001). In addition, COP displacement was delayed in the CLBP group (control: - 0.035 ± 0.021 s; CLBP: - 0.015 ± 0.009 s, t = 3; p = 0.003) and presented a smaller amplitude during APA COPAPA [control: 0.444 cm (0.187; 0.648); CLBP: 0.228 cm (0.096; 0.310), U = 53, p = 0.012]. The CLBP group required a longer time to reach the maximum displacement after the perturbation (control: 0.211 ± 0.047 s; CLBP 0.296 ± 0.078 s, t = 3.582, p = 0.0013). This indicates that CLBP elderly patients have impairments to recover their postural control and less efficient anticipatory adjustments during the compensatory phase. Our results suggest that people with CLBP have altered feedforward hip and ankle muscle control, as shown from the SOL, ST, and RT muscle onset. This study is the first study in the field of aging that investigates the postural adjustments of an elderly population with CLBP. Clinical assessment of this population should consider postural stability as part of a rehabilitation program.- Published
- 2021
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9. Assessing Interlimb Jump Asymmetry in Young Soccer Players: The My Jump 2 App.
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Barbalho M, Kleiner AFR, Callegari B, de Lima RC, da Silva Souza G, de Athayde Costa E Silva A, and Coswig VS
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- Adolescent, Exercise Test, Humans, Male, Reproducibility of Results, Young Adult, Athletic Performance, Mobile Applications, Soccer
- Abstract
Background: Jumps are important evaluation tools for muscle strength and power and for interlimb asymmetries. Different jump tests are well related to athletic performance, prediction of injury risk, and common motor gestures of several sports such as soccer. Low-cost mobile applications (apps) have gained popularity for this measure. The authors hypothesized that the My Jump 2 app would be a valid tool to assess drop-jump performance and interlimb asymmetry in soccer players., Methods: Eleven male soccer players took part in this study (18.2 [1.3] y, 69.9 [9.5] kg, 174 [6.6] cm). The athletes performed each test twice on a force plate (gold-standard method), while the jumps were recorded through the mobile app. Measures with the My Jump 2 app were applied by 2 evaluators, independently and in duplicate (interrater and intrarater reliability). The agreement analysis between both evaluations was done using an intraclass correlation coefficient and Bland-Altman plots., Results: Compared with the force platform, the app tested showed excellent reliability for the drop jump's flight time and interlimb asymmetry (intraclass correlation coefficient > .98). For interlimb contact-time asymmetry, the values were 18.4 (9.9) and 19.1 (9.9) milliseconds for the My Jump 2 app and the force platform, respectively (P = .88). For flight-time asymmetries, the values were 389.7 (114.3) and 396.8 (112.5) milliseconds for the My Jump 2 app and the force platform, respectively (P = .88)., Conclusion: The My Jump 2 app is a valid tool to assess drop-jump and interlimb asymmetry in soccer players.
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- 2021
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10. Positive Balance Recovery in Ischemic Post-Stroke Patients with Delayed Access to Physical Therapy.
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de Athayde Costa E Silva A, Viana da Cruz Júnior AT, Cardoso do Nascimento NI, Andrade Candeira SR, do Socorro Soares Cardoso Almeida A, Santana de Castro KJ, Costa de Lima R, Generoso Campos Pinho Barroso T, da Silva Souza G, and Callegari B
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- Adult, Aged, Brazil, Exercise Test, Female, Humans, Male, Middle Aged, Postural Balance, Stroke complications, Walking, Exercise Therapy methods, Ischemia rehabilitation, Stroke therapy, Stroke Rehabilitation methods
- Abstract
Background: Since patient's prognosis after stroke depends on its severity, brain location, and type early intervention is strongly recommended., Objective: We aimed to determine whether it is still possible to improve balance in chronic patients, who suffered Intracerebral Hemorrhagic Strokes (ICHS) or Ischemic Strokes (IS), after later intervention., Methods: 34 patients who had unilateral ICHS or IS and involved the motor cortex or sub-cortical areas took part in the study. The patients underwent clinical balance evaluation (using the Berg Balance Scale) and posturographic assessment (with a capacitive pressure platform) at the time of admission to the physiotherapy and at the end of the study. The physiotherapy intervention consisted of 20 sessions of 60 minutes carried out 3 times per week, following standard protocols: stretching; passive range of motion (ROM); active assistive ROM; active ROM; resistance training; coordination and balance activities while sitting and standing, and Large-muscle activities such as walking, treadmill, stationary cycle, combined arm-leg ergometry, arm ergometry, seated stepper and circuit training., Results: In the posturographic assessment, the IS group had significant lower amplitude of center of pressure (COP) anteroposterior displacement, after physical therapy intervention. Also, the 95% confidence ellipse area of the COP and the total COP displacement showed significant interaction between the subtype of stroke and the assessment period, meaning the IS group improved their balance after treatment on the contrary of ICHS. The structural analysis of the COP reinforced these results. On the other hand, no difference was observed in the clinical scale, between the assessment periods, for any subtype of stroke., Conclusion: Only IS patients have shown balance improvements after conventional intervention. COP measurements are more sensible to assess balance in chronic patients than Berg Balance Scale., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2020 Anselmo de Athayde Costa e Silva et al.)
- Published
- 2020
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11. Pathway-specific light adaptation in human electroretinograms.
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Brasil A, Tsai TI, da Silva Souza G, Herculano AM, Ventura DF, de Lima Silveira LC, and Kremers J
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- Adult, Color, Electroretinography, Female, Healthy Volunteers, Humans, Luminescence, Male, Photic Stimulation, Adaptation, Ocular physiology, Dark Adaptation physiology, Retinal Cone Photoreceptor Cells physiology
- Abstract
The cellular origins of slow ERG changes during light adaptation following a dark-adapted state are still unclear. To study light adaptation, six healthy, normal trichromats were dark-adapted for 30 min prior to full-field ERG recordings to sinusoidal stimuli that isolate responses of the L- or M-cones or that stimulate luminance and chromatic mechanisms at 12 or 36 Hz. Recordings were performed for 16 min with 2-min intervals after onset of a constant background. Generally, the responses were sine-wave-like, and the first harmonic (fundamental) component dominated the Fourier spectrum except for the 12-Hz luminance stimulus in which two components, a sine-wave-like component and a transient component, determined the response profiles, leading to large second harmonic components. The amplitude of the first harmonic component (F) increased as a function of the light-adaptation time except for the 12-Hz luminance stimulus at which the F component decreased as a function of the light-adaptation period. The phase of the first harmonic component changed only slightly (less than 30°) during the light-adaptation period for all stimuli conditions. The L/M ratio in luminance reflecting ERGs decreased with increasing adaptation time. Our present data suggest that the light-adaptation process mainly reflects changes in the luminance pathway. The responses to 12-Hz luminance stimuli are determined by two different luminance driven pathways with different adaptation characteristics.
- Published
- 2019
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12. Cross-sectional study to assess the association of color vision with mercury hair concentration in children from Brazilian Amazonian riverine communities.
- Author
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Dos Santos Freitas J, da Costa Brito Lacerda EM, da Silva Martins ICV, Rodrigues D Jr, Bonci DMO, Cortes MIT, Corvelo TCO, Ventura DF, de Lima Silveira LC, da Conceição Nascimento Pinheiro M, and da Silva Souza G
- Subjects
- Aging physiology, Brazil, Child, Color Perception Tests, Color Vision physiology, Cross-Sectional Studies, Female, Geography, Medical statistics & numerical data, Humans, Male, Water Pollutants, Chemical analysis, Color Vision drug effects, Hair chemistry, Mercury analysis, Mercury toxicity
- Abstract
Background: Mercury exposure in the Brazilian Amazon region has been an important concern since the 1980s, when gold mining activities contaminated many Amazonian river basins and the fish therein. Mercury exposure in humans can lead to changes in neural function. The visual system has been used as a functional indicator of methylmercury (organic) and mercury vapour (inorganic) toxicity. Children are particularly vulnerable to this metal exposure., Objective: To compare the color vision of children from riverine communities of mercury-exposed (Tapajós basin) and non-exposed Amazonian rivers (Tocantins basin)., Methods: The study sample was 176 children, aged 7-14 years old. Children from two locations in the mercury-exposed Tapajós river basin, Barreiras (n = 71) and São Luiz do Tapajos (n = 41), were compared to children from Limoeiro do Ajuru (n = 64), a non-exposed area in the Tocantins river basin. No caregiver reported that any children had contact with mercury vapour during their lifetime, and probably most of the mercury in their bodies was obtained by fish consumption. Because of this, we decided to evaluate the mercury exposure by total mercury levels in hair samples, a good marker for organic mercury, and not in the urine, a marker for inorganic mercury. Color vision was assessed by the Lanthony Desaturated D-15 test. We used the Vingrys and King-Smith method (1988) to quantify the hue ordering test. The primary visual outcomes from this analysis were C-index (magnitude of the hue ordering error) and angle of the hue ordering., Results: The Tapajós children had a higher mean hair mercury level (mean: 4.5 μg/g; range: 0.26-22.38 μg/g) than that of Tocantins children (mean: 0.49 μg/g; range: 0.03-1.91 μg/g) (p < 0.05). Mean difference was approximately 4.01 μg/g with a 95% confidence interval of 2.79-5.23. The results of the Lanthony D-15d test showed no significant difference between the C-index mean values of the Tapajós and Tocantins groups (p > 0.05). There was a weak linear correlation in the average C-index obtained from both eyes and the total mercury concentration. Multiple logistic regression analysis indicated that the location of the community and the age had a greater influence on the visual outcomes than the sex of the children and within-locale variation in mercury concentration., Conclusion: Our results suggest a difference in one aspect of vision, that is, color vision, between children living in two different river basins in the Brazilian Amazon. The association may be related to Hg exposure but also appeared related to the location of the community and age., (Copyright © 2018 Elsevier B.V. All rights reserved.)
- Published
- 2018
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13. A novel nonsense mutation in the tyrosinase gene is related to the albinism in a capuchin monkey (Sapajus apella).
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Galante Rocha de Vasconcelos FT, Hauzman E, Dutra Henriques L, Kilpp Goulart PR, de Faria Galvão O, Sano RY, da Silva Souza G, Lynch Alfaro J, de Lima Silveira LC, Fix Ventura D, and Oliveira Bonci DM
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- Albinism enzymology, Albinism genetics, Animals, Female, Male, Monkey Diseases enzymology, Phenotype, Phylogeny, Pigmentation genetics, Albinism veterinary, Cebus, Codon, Nonsense genetics, Monkey Diseases genetics, Monophenol Monooxygenase genetics
- Abstract
Background: Oculocutaneous Albinism (OCA) is an autosomal recessive inherited condition that affects the pigmentation of eyes, hair and skin. The OCA phenotype may be caused by mutations in the tyrosinase gene (TYR), which expresses the tyrosinase enzyme and has an important role in the synthesis of melanin pigment. The aim of this study was to identify the genetic mutation responsible for the albinism in a captive capuchin monkey, and to describe the TYR gene of normal phenotype individuals. In addition, we identified the subject's species., Results: A homozygous nonsense mutation was identified in exon 1 of the TYR gene, with the substitution of a cytosine for a thymine nucleotide (C64T) at codon 22, leading to a premature stop codon (R22X) in the albino robust capuchin monkey. The albino and five non-albino robust capuchin monkeys were identified as Sapajus apella, based on phylogenetic analyses, pelage pattern and geographic provenance. One individual was identified as S. macrocephalus., Conclusion: We conclude that the point mutation C64T in the TYR gene is responsible for the OCA1 albino phenotype in the capuchin monkey, classified as Sapajus apella.
- Published
- 2017
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14. Temporal dissociation between sodium depletion and sodium appetite appearance: Involvement of inhibitory and stimulatory signals.
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Margatho LO, Porcari CY, Macchione AF, da Silva Souza GD, Caeiro XE, Antunes-Rodrigues J, Vivas L, and Godino A
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- Administration, Oral, Aldosterone blood, Animals, Appetite drug effects, Drinking Behavior drug effects, Glucose administration & dosage, Male, Methysergide pharmacology, Oncogene Proteins v-fos metabolism, Oxytocin metabolism, Parabrachial Nucleus drug effects, Rats, Rats, Wistar, Renin blood, Saline Solution, Hypertonic administration & dosage, Serotonin metabolism, Serotonin Antagonists pharmacology, Time Factors, Water-Electrolyte Balance, Appetite physiology, Brain metabolism, Drinking Behavior physiology, Sodium metabolism
- Abstract
Our aim was to analyze the participation of inhibitory and stimulatory signals in the temporal dissociation between sodium depletion (SD) induced by peritoneal dialysis (PD) and the appearance of sodium appetite (SA), particularly 2h after PD, when the rats are hypovolemic/natremic but SA is not evident. We investigated the effects of bilateral injections of the serotonin (5-HT) receptor antagonist, methysergide, into the lateral parabrachial nucleus (LPBN) on hypertonic NaCl and water intake 2h vs. 24h after PD. We also studied plasma renin activity (PRA) and aldosterone (ALDO) concentration 2h vs. 24h after PD. Additionally, we combined the analysis of brain Fos immunoreactivity (Fos-ir) with the detection of double immunoreactivity in 5HT and oxytocinergic (OT) cells 2h after PD. Bilateral LPBN injections of methysergide (4μg/200nl at each site) increased NaCl intake when tested 2h after PD compared to controls. We found a significant increase in PRA and ALDO concentration after PD but no differences between 2 and 24h after PD. We also found for the first time a significant increase 2h after PD in the number of Fos-ir neurons in the brainstem nuclei that have been shown to be involved in the inhibition of SA. In summary, the results show that 5HT-mechanisms in the LPBN modulate sodium intake during the delay of SA when the renin angiotensin aldosterone system (RAAS) is increased. In addition, the activation of brainstem areas previously associated with the satiety phase of SA is in part responsible for the temporal dissociation between SD and behavioral arousal., (Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.)
- Published
- 2015
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