Percorrer por autor "Rocha, Isabel"
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- Como manuais escolares abordam o tema números racionaisPublication . Brocardo, Joana; Delgado, Catarina; Segurado, Irene; Rocha, Isabel; Pires, Manuela
- Constructing multiplication: different strategies used by pupilsPublication . Brocardo, Joana; Serrazina, Lurdes; Rocha, IsabelThe Project “Number sense development: curricular demands and perspectives” aims to study the development of number sense in elementary school (5 to 12 years old). This paper presents a discussion based on one of the six case studies developed by the project. We will focuses on the strategies used by 7-years old pupils when solving multiplication problems, namely on the awareness of existence of different strategies and the inclination to utilize an efficient representation or method.
- Dose-dependent cognitive decline, anxiety, and locomotor impairments induced by doxorubicin : evidence from an animal modelPublication . Amaro-Leal, Ângela; Afonso, Ana I.; Machado, Filipa; Shvachiy, Liana; Rocha, Isabel; Outeiro, Tiago F.; Geraldes, VeraCognitive impairment and anxiety are common side effects of chemotherapy, particularly with the use of doxorubicin (DOX), known as “chemobrain”. This study aimed to examine the dose-dependent effects of DOX on cognitive decline, anxiety, and locomotor activity in healthy female Wistar rats. The rats were divided into groups receiving low (2 mg/kg), intermediate (4 mg/kg), and high (5 mg/kg) doses of DOX for four weeks, alongside a control group. Behavioral tests, including open field, elevated plus maze, and Y-maze tests, assessed anxiety, locomotion, and cognitive performance, while brain tissue analysis evaluated neuroinflammation using markers such as GFAP and Iba-1. The results showed that all doses of DOX induced anxiety-like behavior, reduced locomotion, and caused neuroinflammation in the hippocampus, with more severe effects at higher doses. Notably, high-dose DOX also caused short-term memory deficits. These findings highlight the dose-dependent nature of DOX’s impact on behavior and cognition, suggesting that DOX plays a key role in the development of cognitive symptoms during chemotherapy. Further research is needed to understand the mechanisms behind these effects and to explore potential interventions.
- Doxorubicin dose-dependent impact on physiological balance : a holistic approach in a rat modelPublication . Afonso, Ana I.; Amaro-Leal, Ângela; Machado, Filipa; Rocha, Isabel; Geraldes, VeraDoxorubicin (DOX) is commonly used in several chemotherapies to treat various cancers, but it is known to cause cardiotoxicity and cardiac symptoms. Autonomic dysfunction is thought to contribute to the cardiotoxic effects of DOX, but the specific dose required to disrupt homeostatic processes is still unclear and is influenced by numerous factors. This study aimed to investigate how the DOX dosage affects autonomic function and physiological parameters, to elucidate the neurocardiac mechanisms underlying the observed cardiovascular side effects. Wistar rats were treated with DOX for four weeks and divided into three dosing groups: DOX8 (2 mg/kg/week), DOX16 (4 mg/kg/week), and DOX20 (5 mg/kg/week). A control group received NaCl 0.9% saline (1 mL/kg/week). In an acute experiment, we recorded blood pressure (BP), electrocardiogram, heart rate (HR), and respiratory rate (RF). Baroreflex gain and chemoreflex sensitivity were calculated, and cardiac tissue was analyzed with picrosirius histochemistry to measure collagen content. Our results showed that the LF/HF ratio, indicative of autonomic activity, was altered along with hypotension and bradycardia at a cumulative DOX dose threshold of 16 mg/kg. We observed a positive correlation between DOX dose and BP, HR, urinary norepinephrine, LF/HF ratio, and fibrotic heart area. Lower LF/HF ratios were associated with high DOX doses, reflecting drug-induced impairment of autonomic control of HR. This study provides valuable insights into the dose-dependent effects of DOX on physiological parameters and the development of cardiovascular dysfunction. These findings are critical, which is important for optimizing the management and therapeutic strategies for patients undergoing DOX-based chemotherapy.
- Gender-specific effects on the cardiorespiratory system and neurotoxicity of intermittent and permanent low-level lead exposuresPublication . Shvachiy, Liana; Amaro-Leal, Ângela; Machado, Filipa; Rocha, Isabel; Outeiro, Tiago F.; Geraldes, VeraLead exposure is a significant health concern, ranking among the top 10 most harmful substances for humans. There are no safe levels of lead exposure, and it affects multiple body systems, especially the cardiovascular and neurological systems, leading to problems such as hypertension, heart disease, cognitive deficits, and developmental delays, particularly in children. Gender differences are a crucial factor, with women’s reproductive systems being especially vulnerable, resulting in fertility issues, pregnancy complications, miscarriages, and premature births. The globalization of lead exposure presents new challenges in managing this issue. Therefore, understanding the gender-specific implications is essential for developing effective treatments and public health strategies to mitigate the impact of lead-related health problems. This study examined the effects of intermittent and permanent lead exposure on both male and female animals, assessing behaviours like anxiety, locomotor activity, and long-term memory, as well as molecular changes related to astrogliosis. Additionally, physiological and autonomic evaluations were performed, focusing on baro- and chemoreceptor reflexes. The study’s findings revealed that permanent lead exposure has more severe health consequences, including hypertension, anxiety, and reactive astrogliosis, affecting both genders. However, males exhibit greater cognitive, behavioural, and respiratory changes, while females are more susceptible to chemoreflex hypersensitivity. In contrast, intermittent lead exposure leads to hypertension and reactive astrogliosis in both genders. Still, females are more vulnerable to cognitive impairment, increased respiratory frequency, and chemoreflex hypersensitivity, while males show more reactive astrocytes in the hippocampus. Overall, this research emphasizes the importance of not only investigating different types of lead exposure but also considering gender differences in toxicity when addressing this public health concern.
- Números e álgebra: desenvolvimento curricularPublication . Brocardo, Joana; Delgado, Catarina; Mendes, Fátima; Rocha, Isabel; Serrazina, Lurdes
- Um projecto centrado no sentido do númeroPublication . Brocardo, Joana; Serrazina, Lurdes; Rocha, Isabel; Mendes, Fátima; Menino, Hugo; Ferreira, ElviraNesta comunicação faremos uma apresentação global do projecto “Desenvolvendo o sentido do número: Perspectivas e exigências curriculares”. Para além da fundamentação teórica e da metodologia são apresentados resumidamente dois dos estudos de caso realizados procurando ilustrar os dados obtidos com a realização do projecto focando três aspectos principais: a organização das aprendizagens a partir das produções dos alunos, as características das tarefas e o papel do professor.