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1.
J Pharmacol Exp Ther ; 390(2): 250-259, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-38866563

RESUMO

Mutations in the GNAO1 gene, which encodes the abundant brain G-protein Gα o, result in neurologic disorders characterized by developmental delay, epilepsy, and movement abnormalities. There are over 50 mutant alleles associated with GNAO1 disorders; the R209H mutation results in dystonia, choreoathetosis, and developmental delay without seizures. Mice heterozygous for the human mutant allele (Gnao1 +/R209H) exhibit hyperactivity in open field tests but no seizures. We developed self-complementary adeno-associated virus serotype 9 (scAAV9) vectors expressing two splice variants of human GNAO1 Gα o isoforms 1 (GoA, GNAO1.1) and 2 (GoB, GNAO1.2). Bilateral intrastriatal injections of either scAAV9-GNAO1.1 or scAAV9-GNAO1.2 significantly reversed mutation-associated hyperactivity in open field tests. GNAO1 overexpression did not increase seizure susceptibility, a potential side effect of GNAO1 vector treatment. This represents the first report of successful preclinical gene therapy for GNAO1 encephalopathy applied in vivo. Further studies are needed to uncover the molecular mechanism that results in behavior improvements after scAAV9-mediated Gα o expression and to refine the vector design. SIGNIFICANCE STATEMENT: GNAO1 mutations cause a spectrum of developmental, epilepsy, and movement disorders. Here we show that intrastriatal delivery of scAAV9-GNAO1 to express the wild-type Gα o protein reduces the hyperactivity of the Gnao1 +/R209H mouse model, which carries one of the most common movement disorder-associated mutations. This is the first report of a gene therapy for GNAO1 encephalopathy applied in vivo on a patient-allele model.


Assuntos
Dependovirus , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP , Heterozigoto , Animais , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/genética , Camundongos , Dependovirus/genética , Humanos , Masculino , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , Hipercinese/genética , Mutação , Terapia Genética/métodos , Camundongos Endogâmicos C57BL , Locomoção/genética
2.
J Neurophysiol ; 127(3): 607-622, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35080448

RESUMO

GNAO1 encodes Gαo, a heterotrimeric G protein α subunit in the Gi/o family. In this report, we used a Gnao1 mouse model "G203R" previously described as a "gain-of-function" Gnao1 mutant with movement abnormalities and enhanced seizure susceptibility. Here, we report an unexpected second mutation resulting in a loss-of-function Gαo protein, and describe alterations in central synaptic transmission. Whole cell patch clamp recordings from Purkinje cells (PCs) in acute cerebellar slices from Gnao1 mutant mice showed significantly lower frequencies of spontaneous and miniature inhibitory postsynaptic currents (sIPSCs and mIPSCs) compared with WT mice. There was no significant change in sEPSCs or mEPSCs. Whereas mIPSC frequency was reduced, mIPSC amplitudes were not affected, suggesting a presynaptic mechanism of action. A modest decrease in the number of molecular layer interneurons was insufficient to explain the magnitude of IPSC suppression. Paradoxically, Gi/o inhibitors (pertussis toxin) enhanced the mutant-suppressed mIPSC frequency and eliminated the difference between WT and Gnao1 mice. Although GABAB receptor regulates mIPSCs, neither agonists nor antagonists of this receptor altered function in the mutant mouse PCs. This study is an electrophysiological investigation of the role of Gi/o protein in cerebellar synaptic transmission using an animal model with a loss-of-function Gi/o protein.NEW & NOTEWORTHY This report reveals the electrophysiological mechanisms of a movement disorder animal model with monoallelic Gnao1 loss. This study illustrates the role of Gαo protein in regulating GABA release in mouse cerebellum. This study could also facilitate the discovery of new drugs or drug repurposing for GNAO1-associated disorders. Moreover, since GNAO1 shares pathways with other genes related to movement disorders, developing drugs for the treatment of GNAO1-associated movement disorders could further the pharmacological intervention for other monogenic movement disorders.


Assuntos
Transtornos dos Movimentos , Células de Purkinje , Animais , Cerebelo/fisiologia , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/genética , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Camundongos , Células de Purkinje/fisiologia , Transmissão Sináptica/fisiologia , Ácido gama-Aminobutírico/metabolismo
3.
J Sports Sci Med ; 17(4): 571-579, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30479525

RESUMO

This study aimed to provide the first description of the whole-body bioimpedance vector of nine non-professional triathletes, and to assess body mass (BM) and vector variations evoked by an ultra-endurance triathlon event. Anthropometric and bioelectrical assessments were performed before (PRE), after (POST), and 48 hours following the race (POST48h). Bioimpedance vector analysis (BIVA) showed triathletes' vectors placed to the left of the major axis and mostly outside the 50% tolerance ellipse of the reference population. Vector migration in POST indicated dehydration, paralleled by a decrease in BM (p = 0.0001). Increased hydration status from POST to POST48h was suggested by a reversed vector migration and increased BM (p = 0.0001). Compared to PRE, POST48h values reflected fluid retention by changes in BIVA, while BM was still lower (p = 0.0001). Racing time was positively related to basal resistance -R/h- (r = 0.68; p = 0.04) and bioimpedance -Z/h- (r = 0.68; p = 0.045). Besides, basal R/h and Z/h were positively related to PRE-to-POST changes of R/h and Z/h (r = 0.80; p = 0.009). PRE-to-POST changes of R/h and Z/h were positively related to racing time (r = 0.80, p = 0.01) and internal workload (r = 0.80, p ≤ 0.02). Notwithstanding the lack of significant correlation between BM and bioelectrical parameters, the vector's behavior was explained from a multifactorial perspective (including BM variations) by using multiple regression analysis. On the other hand, BM changes were not related to racing time, internal workload or energy deficit (ranges: r = - 0.46 to 0.65; p = 0.06 to 0.98). In conclusion, these triathletes exhibit a specific bioelectrical distribution. Furthermore, vector migration was consistent with fluid loss induced by the event. Finally, vector analysis seems to provide additional information about hydration changes 48h after the event in comparison with BM alone.


Assuntos
Ciclismo/fisiologia , Peso Corporal , Impedância Elétrica , Corrida/fisiologia , Natação/fisiologia , Adulto , Antropometria , Atletas , Desidratação , Humanos , Masculino , Resistência Física
4.
PLoS One ; 13(11): e0205226, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30496211

RESUMO

PURPOSE: This study compared subcutaneous adipose tissue (SAT) measurements using a skinfold caliper and Renco Lean-Meater Series 12 A-mode portable ultrasound scanner (A-US). It aimed to assess their inter- and intra-rater reliability and measure the agreement between both methods. METHODS: Eighty-four volunteers of different fitness levels were divided into three groups by Æ©6 skinfolds: G1 ≤ 55 mm (n = 33 males); G2 > 55 mm (n = 32 males); G3 = 98.0 ± 52.3 mm (n = 19 females). Triceps, subscapular, biceps, iliac crest, supraspinal, abdominal, front thigh and medial calf were assessed by ultrasound and skinfolds. Two technicians for both tools performed triplicate measures. Intraclass correlation (ICC), technical error of measurement (TEM) and coefficients of variation (CVs) were applied for test-retest and inter-rater reliability. Non-Parametric statistics were used in order to establish possible statistical differences and correlation between skinfolds thickness and uncompressed subcutaneous adipose tissue thickness from ultrasound. The amount of agreement between both methods was assessed with Lin's coefficient and a scatterplot of all site locations. A Bland-Altman plot was constructed to establish limits of agreement between groups and regression analysis was employed to assess the ability of skinfolds to explain the variance of ultrasound. RESULTS: Test-retest ICC for skinfolds and ultrasound were higher than 0.989 and 0.793, respectively. Inter-rater ICC for skinfolds was 0.999 with a 95% CI of 0.995 to 0.999 and for ultrasound was 0.755 with a much larger 95% CI of 0.622 to 0.841. TEMs (> 8.50%) and CVs (> 6.72%) compromised ultrasound reliability. Statistical differences were found in most of the analysed anatomical sites (p < 0.001) except in biceps G2 (Z = -1.150, p = 0.25) and G3 (Z = -1.309, p = 0.19). Good correlations (r > 0.7, p ≤ 0.05) were reported at almost all anatomical sites and groups except for biceps (G1: Rho = 0.26, p = 0.140) and abdominal (G2: Rho = -0.16, p = 0.38; G3: Rho = 0.43, p = 0.068). Lin's concordance correlation coefficient registered low values of agreement between skinfolds and A-mode ultrasound (ranged from-0.009-0.646). The scatterplot and the estimated regression line drawn through the midst of all anatomical sites of the whole sample had a slope of 0.51 and R2 adjusted = 0.62 was obtained. The combined analysis between the Bland-Altman plot and the linear regression showed that specifically in the G2 and G3 groups, as the SAT increases the differences between skinfolds and ultrasounds measurements also increases. CONCLUSIONS: The Renco Lean-Meater ultrasound is not interchangeable with skinfold measures. Its utility is questionable, particularly for assessing SAT in active adult populations. Its poor test-retest and inter-rater reliability as well as the lack of agreement when compared to the skinfolds would exclude the free use of the A-mode ultrasound scanner in its hypothetical replacing of the classical calipers.


Assuntos
Composição Corporal/fisiologia , Músculo Esquelético/fisiologia , Gordura Subcutânea/fisiologia , Ultrassonografia/métodos , Abdome/fisiologia , Adulto , Braço/fisiologia , Gorduras/metabolismo , Feminino , Humanos , Masculino , Dobras Cutâneas
5.
Philos Trans A Math Phys Eng Sci ; 372(2030)2014 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-25368345

RESUMO

Surface sediments at Lakes Fryxell, Vanda and Brownworth in the Antarctic Dry Valleys (ADV) were investigated as analogues for the cold, dry environment on Mars. Sediments were sampled from regions surrounding the lakes and from the ice cover on top of the lakes. The ADV sediments were studied using Raman spectra of individual grains and reflectance spectra of bulk particulate samples and compared with previous analyses of subsurface and lakebottom sediments. Elemental abundances were coordinated with the spectral data in order to assess trends in sediment alteration. The surface sediments in this study were compared with lakebottom sediments (Bishop JL et al. 2003 Int. J. Astrobiol. 2, 273-287 (doi:10.1017/S1473550403001654)) and samples from soil pits (Englert P et al. 2013 In European Planetary Science Congress, abstract no. 96; Englert P et al. 2014 In 45th Lunar and Planetary Science Conf., abstract no. 1707). Feldspar, quartz and pyroxene are common minerals found in all the sediments. Minor abundances of carbonate, chlorite, actinolite and allophane are also found in the surface sediments, and are similar to minerals found in greater abundance in the lakebottom sediments. Surface sediment formation is dominated by physical processes; a few centimetres below the surface chemical alteration sets in, whereas lakebottom sediments experience biomineralization. Characterizing the mineralogical variations in these samples provides insights into the alteration processes occurring in the ADV and supports understanding alteration in the cold and dry environment on Mars.

6.
Cambios rev. méd ; 17(2): 65-70, 28/12/2018. tab
Artigo em Espanhol | LILACS | ID: biblio-1005243

RESUMO

INTRODUCCIÓN. La asfixia es causa de morbimortalidad neonatal, deja secuelas motoras y cognitivas. Las enfermeras atienden a recién nacidos desde el nacimiento, participan en su reanimación para evitar las implicancias que aquella conlleva. OBJETIVO. Evaluar conocimientos y práctica de reanimación neonatal de las enfermeras del Servicio de Neonatología, Hospital Regional Docente de Cajamarca. MATERIALES Y MÉTODOS. Estudio descriptivo, transversal, en enfermeras que firmaron el consentimiento informado. Se usó un cuestionario y lista de cotejo. RESULTADOS. El 22,9% de enfermeras obtuvieron más del 80% de respuestas correctas en el cuestionario, dentro de ellas el 22,6% con especialidad en Neonatología, el 50% en Cuidados Intensivos Neonatales y sólo el 10% sin especialidad; el 16,7% de las enfermeras de la subunidad de Atención Inmediata, el 10% de Intermedios, y el 44% de la Unidad de Cuidados Intensivos Neonatal aprobaron el cuestionario. Más de la mitad de las que alcanzaron el puntaje establecido estuvieron entre los 35 y 43 años de edad, y con tiempo de labor en el Servicio de Neonatología entre 0 y 5 años; todas las enfermeras que aprobaron tuvieron al menos una capacitación en reanimación neonatal. El puntaje promedio de conocimientos y práctica de reanimación fue de 19,5 puntos y 10,0 puntos respectivamente. CONCLUSIÓN. Los conocimientos de reanimación cardiopulmonar neonatal de las enfermeras fueron óptimos en casi la quinta parte de ellas mientras que la práctica fue sub óptima en todas.


INTRODUCTION. Asphyxia is a cause of neonatal morbidity and mortality, leaving motor and cognitive sequelae. Nurses attend to newborns from birth, participate in their resuscitation to avoid the implications that this entails. OBJECTIVE. WedxTo evaluate knowledge and practice of neonatal resuscitation of nurses of the Neonatology Service, Regional Teaching Hospital of Cajamarca. MATERIALS AND METHODS. Descriptive, cross-sectional study in nurses who signed informed consent. A questionnaire and checklist was used. RESULTS. 22,9% of nurses obtained more than 80% of correct answers in the questionnaire , among them 22,6% with specialty in neonatology, 50% in Neonatal Intensive Care and only 10% without specialty; 16,7% of nurses in the Immediate Care Sub-Unit, 10% of Intermedios, and 44% of the Neonatal Intensive Care Unit approved the questionnaire. More than half of those who reached the established score were between 35 and 43 years old, and with work time in the Neonatology Service between 0 and 5 years; All the nurses who passed had at least one training in neonatal resuscitation. The average knowledge score and resuscitation practice was 19,5 and 10,0 points respectively. CONCLUSION. The knowledge of neonatal cardiopulmonary resuscitation of nurses was optimal in almost a fifth of them while the practice was sub optimal in all.


Assuntos
Recém-Nascido , Asfixia Neonatal , Ressuscitação , Recém-Nascido , Reanimação Cardiopulmonar , Conhecimento , Cuidados de Enfermagem
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