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3.
Folia Microbiol (Praha) ; 69(1): 121-131, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37526803

RESUMO

The effectiveness of Methylobacterium symbioticum in maize and strawberry plants was measured under different doses of nitrogen fertilisation. The biostimulant effect of the bacteria was observed in maize and strawberry plants treated with the biological inoculant under different doses of nitrogen fertiliser compared to untreated plants (control). It was found that bacteria allowed a 50 and 25% decrease in the amount of nitrogen applied in maize and strawberry crops, respectively, and the photosynthetic capacity increased compared with the control plant under all nutritional conditions. A decrease in nitrate reductase activity in inoculated maize plants indicated that the bacteria affects the metabolism of the plant. In addition, inoculated strawberry plants grown with a 25% reduction in nitrogen had a higher concentration of nitrogen in leaves than control plants under optimal nutritional conditions. Again, this indicates that Methylobacterium symbioticum provide an additional supply of nitrogen.


Assuntos
Fragaria , Methylobacterium , Zea mays/microbiologia , Fragaria/metabolismo , Methylobacterium/metabolismo , Nitrogênio/metabolismo , Fotossíntese , Produtos Agrícolas
4.
Clin Kidney J ; 16(11): 2011-2022, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37915894

RESUMO

Background: Genetic causes are increasingly recognized in patients with focal segmental glomerulosclerosis (FSGS), but it remains unclear which patients should undergo genetic study. Our objective was to determine the frequency and distribution of genetic variants in steroid-resistant nephrotic syndrome FSGS (SRNS-FSGS) and in FSGS of undetermined cause (FSGS-UC). Methods: We performed targeted exome sequencing of 84 genes associated with glomerulopathy in patients with adult-onset SRNS-FSGS or FSGS-UC after ruling out secondary causes. Results: Seventy-six patients met the study criteria; 24 presented with SRNS-FSGS and 52 with FSGS-UC. We detected FSGS-related disease-causing variants in 27/76 patients (35.5%). There were no differences between genetic and non-genetic causes in age, proteinuria, glomerular filtration rate, serum albumin, body mass index, hypertension, diabetes or family history. Hematuria was more prevalent among patients with genetic causes. We found 19 pathogenic variants in COL4A3-5 genes in 16 (29.3%) patients. NPHS2 mutations were identified in 6 (16.2%) patients. The remaining cases had variants affecting INF2, OCRL, ACTN4 genes or APOL1 high-risk alleles. FSGS-related genetic variants were more common in SRNS-FSGS than in FSGS-UC (41.7% vs 32.7%). Four SRNS-FSGS patients presented with NPHS2 disease-causing variants. COL4A variants were the most prevalent finding in FSGS-UC patients, with 12 patients carrying disease-causing variants in these genes. Conclusions: FSGS-related variants were detected in a substantial number of patients with SRNS-FSGS or FSGS-UC, regardless of age of onset of disease or the patient's family history. In our experience, genetic testing should be performed in routine clinical practice for the diagnosis of this group of patients.

5.
Pharmaceutics ; 15(8)2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37631349

RESUMO

Treatment with second-generation antipsychotics (SGAs) can cause obesity and other cardiometabolic disorders linked to D2 receptor (DRD2) and to genotypes affecting dopaminergic (DA) activity, within reward circuits. We explored the relationship of cardiometabolic alterations with single genetic polymorphisms DRD2 rs1799732 (NG_008841.1:g.4750dup -> C), DRD2 rs6277 (NG_008841.1:g.67543C>T), COMT rs4680 (NG_011526.1:g.27009G>A), and VNTR in both DRD4 NC_000011.10 (637269-640706) and DAT1 NC_000005.10 (1392794-1445440), as well as with a multilocus genetic profile score (MLGP). A total of 285 psychiatric patients treated with SGAs for at least three months were selected. Cardiometabolic parameters were classified according to ATP-III and WHO criteria. Blood samples were taken for routinely biochemical assays and PCR genotyping. Obesity (BMI, waist (W)), high diastolic blood pressure (DBP), and hypertriglyceridemia (HTG) were present in those genetic variants related to low dopaminergic activity: InsIns genotype in rs1799732 (BMI: OR: 2.91 [1.42-5.94]), DRD4-VNTR-L allele (W: OR: 1.73 [1.04-2.87]) and 9R9R variant in DAT1-VNTR (W: OR: 2.73 [1.16-6.40]; high DBP: OR: 3.33 [1.54-7.31]; HTG: OR: 4.38 [1.85-10.36]). A low MLGP score indicated a higher risk of suffering cardiometabolic disorders (BMI: OR: 1.23 [1.05-1.45]; W: OR: 1.18 [1.03-1.34]; high DBP: OR: 1.22 [1.06-1.41]; HTG: OR: 1.20 [1.04-1.39]). The MLGP score was more sensitive for detecting the risk of suffering these alterations. Low dopaminergic system function would contribute to increased obesity, BDP, and HTG following long-term SGA treatment.

6.
Sensors (Basel) ; 23(13)2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37447921

RESUMO

Nowadays, cyber-physical systems (CPSs) are composed of more and more agents and the demand for designers to develop ever larger multi-agent systems is a fact. When the number of agents increases, several challenges related to control or communication problems arise due to the lack of scalability of existing solutions. It is important to develop tools that allow control strategies evaluation of large-scale systems. In this paper, it is considered that a CPS is a heterogeneous robot multi-agent system that cooperatively performs a formation task through a wireless network. The goal of this research is to evaluate the system's performance when the number of agents increases. To this end, two different frameworks developed with the open-source tools Gazebo and Webots are used. These frameworks enable combining both real and virtual agents in a realistic scenario allowing scalability experiences. They also reduce the costs required when a significant number of robots operate in a real environment, as experiences can be conducted with a few real robots and a higher number of virtual robots by mimicking the real ones. Currently, the frameworks include several types of robots, such as the aerial robot Crazyflie 2.1 and differential mobile robots Khepera IV used in this work. To illustrate the usage and performance of the frameworks, an event-based control strategy for rigid formations varying the number of agents is analyzed. The agents should achieve a formation defined by a set of desired Euclidean distances to their neighbors. To compare the scalability of the system in the two different tools, the following metrics have been used: formation error, CPU usage percentage, and the ratio between the real time and the simulation time. The results show the feasibility of using Robot Operating System (ROS) 2 in distributed architectures for multi-agent systems in experiences with real and virtual robots regardless of the number of agents and their nature. However, the two tools under study present different behaviors when the number of virtual agents grows in some of the parameters, and such discrepancies are analyzed.


Assuntos
Robótica , Robótica/métodos , Espécies Reativas de Oxigênio , Software , Simulação por Computador
7.
PLoS One ; 17(11): e0277485, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36449451

RESUMO

INTRODUCTION: This paper examines the convergence of the opinions of European higher education institution (HEI) experts on possible implementation of dual career policies and provision areas at university level. METHODS: An online 32-item questionnaire encompassing 26 dual career aspects collected the opinion of European HEI experts as the last phase of a Delphi method preceded by i) focus groups with student-athletes who aimed to identify needs for dual careers and ii) a workshop with 21 dual career experts to generate the statements to be included in the survey. Seventy-one HEI experts from 12 EU member states participated in the survey, rating each dual career aspect identified in previous phases. RESULTS: The relative position of each aspect has been plotted based on relevance (x-axis) and feasibility (y-axis). The Quadrant IV of the resulting scatterplots identified the following nine aspects rated as highly relevant and highly feasible for implementation: tutorship/mentorship, psychological support, programmes based on integration of academic departments and sports services, and adaptable programmes to the needs of each student-athletes (assistance/tutorship area), individual study plans and distance learning (curricula requirements area), publicity for student-athletes and initiatives for increasing the awareness of student-athletes and knowledge of dual career issues (social support area), and access to educational facilities (logistic support area). DISCUSSION AND CONCLUSIONS: The HEI experts' views represent a coherent and useful starting point to develop a deep understanding of the considered 26 aspects founded on a phenomenological lifeworld-led approach and emphasizes the need for a minimum standard for dual career policies and provisions.


Assuntos
Resolução de Problemas , Instituições Acadêmicas , Humanos , Universidades , Estudantes , Atletas
8.
PLoS One ; 17(2): e0264175, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35213599

RESUMO

Previous studies have found that student-athletes (S-As) have difficulties in achieving dual career (DC) success. However, no studies have analysed the opinion of the S-As on the functioning of DC with a qualitative methodology. The aim of the present work was to collect the opinions of elite university S-As in relation to DC policy adopted by their academic institutions in different European countries. In total, 77 athletes (F = 35, M = 42; age range: 20-25 years) participated in 15 national face-to-face focus groups in five different countries, to discuss aspects that higher education institutes should implement in relation to: 1) the athletes' needs; 2) assistance/tutorship: 2) curricula requirements; 3) financial support; 4) logistic support; 5) social support; and 6) dual career policies. Fifty of the athletes competed in individual sports and twenty-seven team sports. Of them, 57 was enrolled at undergraduate, 17 was enrolled in a master and 3 in a PhD. The athletes were presented with 13 open-ended questions one by one, and were ensured freedom to interact. All the discussions were recorded. After this, a general discussion took place in which the participants identified and agreed on a final list of statements from their focus group deemed to be relevant to DC athletes as university students. Then, at a consensus meeting, the findings were combined, repetitions were eliminated, and fragmented statements were condensed into broader ones. A final list of 31 statements, organized in six related content units, were identified in relation to the athletes' needs (n = 5), assistance/tutorship (n = 5), curricula requirements (n = 4), financial support (n = 4), logistic support (n = 4), social support (n = 6), and DC policies (n = 3), respectively. In conclusion, this cross-national qualitative research study synthesized the S-As views about their needs and the most relevant DC policies and provisions that higher education institutes should provide to ensure them with positive academic experiences towards the achievement of a degree.


Assuntos
Atletas , Escolha da Profissão , Currículo , Esportes , Estudantes , Universidades , Adulto , Europa (Continente) , Feminino , Humanos , Masculino
9.
IEEE J Biomed Health Inform ; 26(6): 2814-2821, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35015657

RESUMO

Perinatal asphyxia represents a major medical disorder and is related to around a fourth of all neonatal deaths worldwide. Specific thresholds for lactate or pH levels define the gold standard for detecting hypoxic-ischemic events as physiological abnormalities. In contrast to current gold standard, we analyze the systemic picture, represented by the whole set of biochemical parameters from blood gas analysis, by multiparametric machine learning algorithms. In a swine model with 22 objects, we investigate the impact of neonatal hypoxic-ischemic encephalopathy on 18 individual physiological parameters. In a first approach, we study the statistical significance of individual parameters by univariate analysis methods. In a second approach, we take the most relevant parameters as input for the development of predictive models by different hybrid and non-hybrid classification algorithms. The predictive power of our multiparametric models outperforms by far the limited performance of pH and lactate as reliable indicators, despite strong correlation with hypoxic-ischemic events. We have been able to detect hypoxic-ischemic events even one hour after the episode, with accuracies close to 100% in contrast to pH or lactate-based diagnosis with 62% and 78%, respectively. By all machine learning algorithms, lactate is recognized as the main contributor due to its longer-term evidence of hypoxia-ischemia episodes. However, substantial improvement of the diagnosis is achieved by predictions based on a systemic picture of different physiological parameters. Our results prove the potential applicability of our method as a support tool for decision-making that will allow obstetricians to identify hypoxic-ischemic episodes more accurately during labor.


Assuntos
Asfixia Neonatal , Quimiometria , Animais , Feminino , Humanos , Hipóxia , Recém-Nascido , Isquemia , Lactatos , Gravidez , Suínos
10.
Front Psychol ; 12: 657671, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33868131

RESUMO

This study aimed to investigate the student-athletes' capability to face the academic, sport, and social challenges during the coronavirus disease 2019 (COVID-19) lockdown and to disclose novel aspects of dual careers. A 32-item online survey encompassing demographic characteristics, sport and university engagement, support and dual-career benefits, physical activity, sitting time, and the time deemed necessary to recover the previous level of performance was developed. Four hundred sixty-seven student-athletes (males: 57%, females: 43%) from 11 countries, competing in 49 different sports (individual: 63.4%, team: 36.6%) at regional (17.5%), national (43.3%), and international (39.2%) levels, and enrolled at high school (21.9%) and university (78.1%) levels completed the survey. During the lockdown, the respondents decreased the time dedicated to sport and academics, although they maintained an active lifestyle. Student-athletes from countries under severe contagion were more likely to train at home, dedicate to academics, and receive support from the coach but less likely receive support from their teachers. With respect to their team sport counterparts, athletes competing in individual sports trained more and were more likely to receive support from their coaches. International athletes showed the highest training time and support from their coaches and as student-athletes. High school students received more support from their coaches and teachers, whereas university students were more likely considering dual careers useful to cope with the COVID-19 pandemic. This study substantiates the relevant role of competitive sports participation in the maintenance of active lifestyles, with student-athletes considering home training and e-learning valuable resources during the lockdown. Furthermore, their sport and academic commitments helped student-athletes cope with the emergency of the COVID-19 pandemic.

11.
Acta otorrinolaringol. esp ; 72(2): 92-100, mar.-abr. 2021. graf, tab
Artigo em Espanhol | IBECS | ID: ibc-202566

RESUMO

ANTECEDENTES Y OBJETIVO: El diagnóstico diferencial de vértigo supone un reto diagnóstico en el ámbito de urgencias. En nuestro centro hemos creado un protocolo de vértigo para ayudar a distinguir las diferentes patologías y su manejo en urgencias. Nuestro objetivo es determinar la eficacia de nuestro protocolo hospitalario en la actitud diagnóstica y terapéutica ante un síndrome vestibular agudo. PACIENTES Y MÉTODOS: Estudio observacional, descriptivo, retrospectivo, sobre pacientes ingresados con diagnóstico de síndrome vestibular agudo en urgencias mediante nuestro protocolo de vértigo de origen dudoso. A todos los pacientes se les realizó una exploración que incluyera el protocolo HINTS y tuvieron un seguimiento mínimo durante seis meses. Se compararon los resultados del estudio de impresiones clínicas por parte de los especialistas, así como la exploración física con los diferentes diagnósticos finales clasificados en periférico, central y otro origen. RESULTADOS: Obtuvimos 97 pacientes con una edad media de 61,46 años. Los diagnósticos finales fueron de 26 pacientes en el grupo periférico (26,8%), 38 en otro origen (39,2%) y 33 en central (34%). En este último se objetivaron accidentes cerebrovasculares en 18 de ellos, siendo el motivo más frecuente de activación del protocolo una discordancia clínico-exploratoria. CONCLUSIONES: Nuestro protocolo ha demostrado ser una herramienta útil para poder diferenciar un posible síndrome vestibular agudo de origen central de uno periférico, evitando la realización de pruebas de imagen de manera innecesaria. La causa más frecuente de activación del protocolo fue la discordancia clínico-exploratoria vista por el otorrino de guardia


BACKGROUND AND OBJECTIVE: Differential diagnosis of vertigo is a diagnostic challenge in the emergency setting. In our centre we have created a vertigo protocol to distinguish the different pathologies and their management in the emergency department. Our goal is to determine the efficacy of our hospital protocol in the diagnostic and therapeutic approach to acute vestibular syndrome. PATIENTS AND METHODS: It is a retrospective descriptive observational study on patients with a diagnosis of acute vestibular syndrome in the emergency department using our unclear origin vertigo protocol. All patients underwent an examination that included the HINTS protocol and had a minimum follow-up of 6 months. The results of the clinical assessments by the specialists were compared, as well as the physical examination with the different final diagnoses classified as peripheral, central and other-origin. RESULTS: We obtained 97 patients, with a mean age of 61.46 years. The final diagnoses were 26 patients for the peripheral group (26.8%), 38 for the other-origin group (39.2%) and 33 for the central group (34%). Stroke was found in 18 of the latter group, clinical-exploratory disagreement being the most frequent reason for activation of the protocol. CONCLUSIONS: Our protocol has proven to be a useful tool to differentiate a possible acute vestibular syndrome of central origin from a peripheral one, avoiding unnecessary imaging tests. The most frequent cause of activation of the protocol was clinical-exploratory disagreement seen by the ENT doctor


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Vertigem/diagnóstico , Vertigem/terapia , Estudos Retrospectivos , Diagnóstico Diferencial , Tomografia Computadorizada por Raios X , Fatores de Risco , Serviço Hospitalar de Emergência , Protocolos Clínicos , Acidente Vascular Cerebral/diagnóstico
12.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32862974

RESUMO

BACKGROUND AND OBJECTIVE: Differential diagnosis of vertigo is a diagnostic challenge in the emergency setting. In our centre we have created a vertigo protocol to distinguish the different pathologies and their management in the emergency department. Our goal is to determine the efficacy of our hospital protocol in the diagnostic and therapeutic approach to acute vestibular syndrome. PATIENTS AND METHODS: It is a retrospective descriptive observational study on patients with a diagnosis of acute vestibular syndrome in the emergency department using our unclear origin vertigo protocol. All patients underwent an examination that included the HINTS protocol and had a minimum follow-up of 6 months. The results of the clinical assessments by the specialists were compared, as well as the physical examination with the different final diagnoses classified as peripheral, central and other-origin. RESULTS: We obtained 97 patients, with a mean age of 61.46 years. The final diagnoses were 26 patients for the peripheral group (26.8%), 38 for the other-origin group (39.2%) and 33 for the central group (34%). Stroke was found in 18 of the latter group, clinical-exploratory disagreement being the most frequent reason for activation of the protocol. CONCLUSIONS: Our protocol has proven to be a useful tool to differentiate a possible acute vestibular syndrome of central origin from a peripheral one, avoiding unnecessary imaging tests. The most frequent cause of activation of the protocol was clinical-exploratory disagreement seen by the ENT doctor.

13.
Int J Mol Sci ; 21(4)2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32074976

RESUMO

In the process of neonatal encephalopathy, oxidative stress and neuroinflammation have a prominent role after perinatal asphyxia. With the exception of therapeutic hypothermia, no therapeutic interventions are available in the clinical setting to target either the oxidative stress or inflammation, despite the high prevalence of neurological sequelae of this devastating condition. The endocannabinoid system (ECS), recently recognized as a widespread neuromodulatory system, plays an important role in the development of the central nervous system (CNS). This study aims to evaluate the potential effect of the cannabinoid (CB) agonist WIN 55,212-2 (WIN) on reactive oxygen species (ROS) and early inflammatory cytokine production after hypoxia-ischemia (HI) in fetal lambs. Hypoxic-ischemic animals were subjected to 60 min of HI by partial occlusion of the umbilical cord. A group of lambs received a single dose of 0.01 µg/kg WIN, whereas non-asphyctic animals served as controls. WIN reduced the widespread and notorious increase in inflammatory markers tumor necrosis factor (TNF)-α and interleukin (IL)-1ß and IL-6 induced by HI, a modulatory effect not observed for oxidative stress. Our study suggests that treatment with a low dose of WIN can alter the profile of pro-inflammatory cytokines 3 h after HI.


Assuntos
Canabinoides/farmacologia , Citocinas/metabolismo , Hipóxia-Isquemia Encefálica/patologia , Estresse Oxidativo/efeitos dos fármacos , Animais , Benzoxazinas/farmacologia , Córtex Cerebral/metabolismo , Córtex Cerebral/fisiologia , Modelos Animais de Doenças , Feminino , Feto/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Morfolinas/farmacologia , Naftalenos/farmacologia , Gravidez , Espécies Reativas de Oxigênio/química , Espécies Reativas de Oxigênio/metabolismo , Receptores de Canabinoides/química , Receptores de Canabinoides/metabolismo , Ovinos , Fator de Necrose Tumoral alfa/metabolismo
14.
Pediatr Res ; 85(4): 539-545, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30675020

RESUMO

BACKGROUND: Newborn pigs offer theoretical advantages for studying newborn hypoxic-ischemic (HI) brain damage because of a development and structure similar to the human brain. However, the correlation between functional features and actual HI brain damage has not been reported. METHODS: Newborn pigs were examined daily for 3 days after a HI insult using amplitude-integrated EEG (aEEG), and a neurobehavioral score enriched with stress and social and object interaction-driven activity evaluation. Brain damage was then assessed using histologic, immunohistochemical, and proton magnetic resonance spectroscopy studies. Brain concentration of several neurotransmitters was determined by HPLC. RESULTS: HI insult led to aEEG amplitude decrease, muscle tone and activity impairment, eating disorders, poor environmental interaction, and increased motionless periods. Basal aEEG amplitude, muscle tone, and general behavior were the best predictive items for histological and biochemical (lactate/N-acetylaspartate ratio) brain damage. Hyperexcitable response to stress correlated inversely with brain damage. Motionless time, which correlated with brain damage severity, was inversely related to brain concentration of dopamine and norepinephrine. CONCLUSION: Standard neurologic examination of brain activity and motor and behavioral performance of newborn pigs is a valuable tool to assess HI brain damage, thus offering a powerful translational model for HI brain damage pathophysiology and management studies.


Assuntos
Eletroencefalografia/métodos , Hipóxia-Isquemia Encefálica/patologia , Exame Neurológico , Animais , Hipóxia-Isquemia Encefálica/fisiopatologia , Índice de Gravidade de Doença , Análise de Sobrevida , Suínos
15.
PLoS One ; 10(5): e0126885, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26010092

RESUMO

INTRODUCTION: Hypoxia-ischemia (HI) is a major perinatal problem that results in severe damage to the brain impairing the normal development of the auditory system. The purpose of the present study is to study the effect of perinatal asphyxia on the auditory pathway by recording auditory brain responses in a novel animal experimentation model in newborn piglets. METHOD: Hypoxia-ischemia was induced to 1.3 day-old piglets by clamping 30 minutes both carotid arteries by vascular occluders and lowering the fraction of inspired oxygen. We compared the Auditory Brain Responses (ABRs) of newborn piglets exposed to acute hypoxia/ischemia (n = 6) and a control group with no such exposure (n = 10). ABRs were recorded for both ears before the start of the experiment (baseline), after 30 minutes of HI injury, and every 30 minutes during 6 h after the HI injury. RESULTS: Auditory brain responses were altered during the hypoxic-ischemic insult but recovered 30-60 minutes later. Hypoxia/ischemia seemed to induce auditory functional damage by increasing I-V latencies and decreasing wave I, III and V amplitudes, although differences were not significant. CONCLUSION: The described experimental model of hypoxia-ischemia in newborn piglets may be useful for studying the effect of perinatal asphyxia on the impairment of the auditory pathway.


Assuntos
Asfixia/fisiopatologia , Vias Auditivas/fisiopatologia , Potenciais Evocados Auditivos do Tronco Encefálico , Hipóxia-Isquemia Encefálica/fisiopatologia , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Humanos , Tempo de Reação
16.
Reprod Sci ; 19(7): 754-63, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22378862

RESUMO

Despite advances in neonatology, the hypoxic-ischemic injury in the perinatal period remains the single most important cause of brain injury in the newborn, leading to death or lifelong sequelae. Using a sheep model of intrauterine asphyxia, we evaluated the correlation between reactive oxygen species (ROS) overproduction, cytokine expression, and apoptotic cell death. Fetal lambs were assigned to sham group, nonasphyctic animals; and hypoxia-ischemia (HI) group, lambs subjected to 60 minutes of HI) by partial cord occlusion and sacrificed 3 hours later. Different brain regions were separated to quantify the number of apoptotic cells and the same territories were dissociated for flow cytometry studies. Our results suggest that the overproduction of ROS and the early increase in cytokine production after HI in fetal lambs correlate in a significant manner with the apoptotic index, as well as with each brain region evaluated.


Assuntos
Apoptose , Encéfalo/metabolismo , Citocinas/metabolismo , Hipóxia Fetal/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima , Animais , Encéfalo/embriologia , Encéfalo/imunologia , Encéfalo/patologia , Moléculas de Adesão Celular/metabolismo , Modelos Animais de Doenças , Feminino , Hipóxia Fetal/imunologia , Hipóxia Fetal/patologia , Hipóxia-Isquemia Encefálica/embriologia , Hipóxia-Isquemia Encefálica/imunologia , Hipóxia-Isquemia Encefálica/patologia , Proteínas do Tecido Nervoso/metabolismo , Neurônios/imunologia , Neurônios/metabolismo , Neurônios/patologia , Especificidade de Órgãos , Distribuição Aleatória , Carneiro Doméstico
17.
Acta Paediatr ; 94(7): 903-11, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16188813

RESUMO

AIM: To evaluate the effect of cerebral hypoxia-ischaemia induced by partial occlusion of the umbilical cord on the relationship of the regional cerebral blood flow and the cerebral cell death in near-term fetal lambs. METHODS: Fifteen near-term lambs were assigned to two hypoxic-ischaemic groups with or without life support (3 h), and a healthy one. Hypoxia-ischaemia was induced by partial occlusion of the umbilical cord (60 min). Routine light and electron microscopy, and the TUNEL method for apoptosis were performed. Regional cerebral blood flow was measured by coloured microspheres. Cardiovascular, gas exchange and pH parameters were also evaluated. RESULTS: Both hypoxic-ischaemic groups produced a transient acidosis and a decrease of base excess in comparison to the healthy group. Cortical and cerebellar zones, where the regional cerebral blood flow values were similar to baseline, showed an increased number of oligodendrocyte-like apoptotic cells. In contrast, in the inner zones, where regional cerebral blood flow was increased, the number of apoptotic cells did not increase. Necrotic neurons were observed in the basal nuclei, mesencephalon, pons and deep cerebellar nuclei. CONCLUSION: Our results suggest that regional cerebral blood flow and the presence of apoptotic cells, 3 h after hypoxic-ischemic injury, are correlated.


Assuntos
Circulação Cerebrovascular , Hipóxia-Isquemia Encefálica/fisiopatologia , Animais , Animais Recém-Nascidos , Apoptose , Fragmentação do DNA , Hipóxia-Isquemia Encefálica/patologia , Marcação In Situ das Extremidades Cortadas , Troca Gasosa Pulmonar , Ovinos
18.
J Cereb Blood Flow Metab ; 24(11): 1267-71, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15545922

RESUMO

Early neurological deterioration (END) is associated with increased mortality and morbidity. Although several predictive factors have been reported, there are little data about the hemodynamic factors. Our aim was to determine the capacity of cerebral hemodynamic reserve (CHR) to predict END. We studied 100 hospitalized patients with a first ever ischemic stroke of the middle cerebral artery (MCA) within the first 24 hours of symptoms onset. END was defined as a drop of at least one point in the Canadian Stroke Scale between admission and 72 hours. The mean flow velocity (mV) in the MCA and the CHR were measured by means of transcranial Doppler within the first 24 hours of admission. The CHR was expressed as the percentage increase in the MCA mV divided by the absolute increase in the end-tidal CO2 pressure in mm Hg after carbogen inhalation. END was observed in 23 patients. Reduced values of the mV in the symptomatic MCA (P = 0.043) and of the CHR in the symptomatic hemisphere (P < 0.001) were significantly associated with END. A CHR of less than 2%/1 mm Hg was independently associated with END (OR 8.45, 95% CI 1.82-39.2) after adjusting for potential confounders. CHR impairment within the first 24 hours of acute ischemic stroke is associated with a higher risk of END. This technique may be useful in selecting patients requiring a more intensive management.


Assuntos
Hemodinâmica , Acidente Vascular Cerebral/patologia , Acidente Vascular Cerebral/fisiopatologia , Idoso , Feminino , Humanos , Masculino , Fatores de Tempo , Ultrassonografia Doppler Transcraniana
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