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- In vitro metabolism of steroid hormones by ovary and hepatopancreas of the crustacean Penaeid shrimp Marsupenaeus japonicusPublication . Summavielle, Teresa; Monteiro, Pedro Ribeiro Rocha; Reis-Henriques, Maria Armanda; Coimbra, João; Monteiro, Pedro; Summavielle, TeresaRadioimmunoassay (RIA) was applied to identify selected metabolites obtained in in vitroincubations of ovarianand hepatopancreatic tissues from female Marsupenaeus japonicusin previtellogenic and vitellogenic maturation stages. Depend-ing on the precursors used, progesterone, 17α-hydroxyprogesterone or testosterone, it was possible to observe the presence of sev-eral enzymatic activities through metabolites detected in incubations. The present study provides evidence that the ovary of theshrimpM. japonicusis capable of synthesising 17β-estradiol from progesterone, evidencing the presence of 17α-hydroxy-lase, C17-C20lyase, 17β-hydroxysteroid dehydrogenase (17β-HSD) and aromatase. Enzymatic activities of aromatase, 3β-HSD and 17α-hydroxylase were detected in hepatopancreas, but not that of C17-C20lyase. These results suggest that 17β-estradiol could be the vitellogenesis stimulating ovarian hormone (VSOH), and together with former in vivoand in vitrostudies this leads us to propose that in fact there may be a physiological role for steroid hormones in the maturation cycleof crustaceans.
- Presence of pain shows greater effect than tendon structural alignment during landing dynamicsPublication . Silvia, Ortega-Cebrián; Silva, Diogo C. F.; Carneiro, Daniela F.; Zárate, Victor; Alves, Leonel A. T.; Guedes, Diana C.; Zárate-Tejero, Carlos A.; Cadellans-Arróniz, Aïda; Montes, António Mesquita; Mesquita Montes, António; Silva, Diogo C. F.; C. Guedes, Diana"Eccentric loading during landing is considered a key factor in the development of patellar tendinopathy and is associated with stiff landings and patellar tendinopathy. This study aims to investigate the relationship between tendon structure, presence of pain, and sex differences in landing kinematics and kinetics during countermovement jumps (CMJ) and tuck jump tests (TJT) in professional volleyball players. Professional volleyball players aged 18 to 30 years old (14 females and 25 males) participated in a cross-sectional study. Data included the Victorian Institute of Sport Assessment Patellar Tendon (VISA-P) questionnaire; patellar tendon ultrasound characterization tissue (UTC) scans, in order to identify groups with misaligned tendon fibers (MTF) or aligned tendon fibers (ATF); and biomechanical assessments for CMJ and TJT. The joint angle (JA) at the lower limb was measured at peak ground reaction force (peak_vGRF) and maximal knee flexion (max_KF). A general linear model was used to evaluate joint JA differences between tendon alignment, pain, and sex variables. Sample t-tests compared peak_vGRF, load time, load rate, and area based on tendon alignment, pain presence, sex, and jump. The statistical significance of p-value is >0.05, and the effect size (ES) was also calculated. The MTF group revealed decreased knee JA during TJT at peak_vGRF (p = 0.01; ES = −0.66) and max_KF (p = 0.02; ES = −0.23). The presence of pain was associated with increased JA during the CMJ, particularly at peak_vGRF and max_KF for trunk, hip, and ankle joints. Females showed decreased peak_vGRF than males. Landing with misaligned tendon fibers showed longer load times compared to aligned tendon fibers (p = 0.021; ES = −0.80). The TJT exhibited a greater load rate than the CMJ (p = 0.00; ES = −0.62). Pain is a critical factor influencing greater JA during landing, particularly at the trunk, hip, and ankle joints in CMJ. Misaligned tendon fibers compromise landing dynamics by increasing trunk JA during TJT. Kinetics varied significantly by sex and jump type, while pain and tendon structure revealed limited differences. "
- Feasibility of 3D body tracking from monocular 2D video feeds in musculoskeletal telerehabilitationPublication . Clemente, Carolina; Chambel, Gonçalo; Silva, Diogo C. F.; Montes, António Mesquita; Pinto, Joana F.; Silva, Hugo Plácido da; Mesquita Montes, António; Silva, Diogo C. F.Musculoskeletal conditions affect millions of people globally; however, conventional treatments pose challenges concerning price, accessibility, and convenience. Many telerehabilitation solutions offer an engaging alternative but rely on complex hardware for body tracking. This work explores the feasibility of a model for 3D Human Pose Estimation (HPE) from monocular 2D videos (MediaPipe Pose) in a physiotherapy context, by comparing its performance to ground truth measurements. MediaPipe Pose was investigated in eight exercises typically performed in musculoskeletal physiotherapy sessions, where the Range of Motion (ROM) of the human joints was the evaluated parameter. This model showed the best performance for shoulder abduction, shoulder press, elbow flexion, and squat exercises. Results have shown a MAPE ranging between 14.9% and 25.0%, Pearson’s coefficient ranging between 0.963 and 0.996, and cosine similarity ranging between 0.987 and 0.999. Some exercises (e.g., seated knee extension and shoulder flexion) posed challenges due to unusual poses, occlusions, and depth ambiguities, possibly related to a lack of training data. This study demonstrates the potential of HPE from monocular 2D videos, as a markerless, affordable, and accessible solution for musculoskeletal telerehabilitation approaches. Future work should focus on exploring variations of the 3D HPE models trained on physiotherapy-related datasets, such as the Fit3D dataset, and post-preprocessing techniques to enhance the model’s performance.
- Altered environmental perception by parental stress and depression vulnerability: impact on mothers and offspringPublication . Alves, Renata L.; Portugal, Camila C.; Lopes, Igor M.; Oliveira, Pedro; Alves, Cecília J.; Barbosa, Fernando; Summavielle, Teresa; Magalhães, Ana; Summavielle, TeresaDepressive mothers often find the mother-child interaction to be challenging. Parental stress may further impair mother-child attachment, which may increase the risk of negative developmental consequences. We used rats with different vulnerability to depression (Wistar and Kyoto) to investigate the impact of stress (maternal separationMS) on maternal behaviour and adolescent offspring cognition. MS in Kyoto dams increased pup-contact, resulting in higher oxytocin levels and lower anxiety-like behaviour after weaning, while worsening their adolescent offspring cognitive behaviour. Whereas MS in Wistar dams elicited higher quality of pup-directed behaviour, increasing Brain-Derived Neurotrophic Factor (BDNF) in the offspring, which seems to have prevented a negative impact on cognition. Hypothalamic oxytocin seems to impact the salience of the social environment cues (as negative for Kyoto) leading to different coping strategies. Our findings highlight the importance of contextual and individual factors in the understanding of the oxytocin role in modulating maternal behaviour and stress regulatory processes.
- Effects of postnatal cocaine exposure and environmental enrichment on rat behavior in a forced swim testPublication . Magalhães, Ana; Summavielle, Teresa; Tavares, Maria Amélia; Sousa, Liliana de; Summavielle, TeresaThis study examined the effects of environmental enrichment on rats exposed to cocaine during the first month of life, in several categories of behavior observed in a forced swim test. Wistar rats were divided in four groups. The first included pups that were subjected to injections of cocaine hydrochloride (15 mg/kg body weight/day, subcutaneously, in two daily doses, from postnatal days 1 to 27) and reared in an enriched environment (CocEE); the second, pups that were subjected to injections of cocaine (as previously described) and reared in a standard environment (CocSE); the third, pups that were subjected to saline injections and reared in an enriched environment (SalEE); the fourth, pups that were subjected to saline injections and reared in a standard environment (SalSE). On postnatal days 26 and 27, rats were tested in a swimming pool in two 5-min sessions. The categories of behavior studied in this work were: fast swim, slow swim, struggling, diving, and immobility. Results showed that postnatal cocaine exposure decreased the time spent on fast swim during the two sessions and increased the immobility behavior during the second session in CocSE pups compared with SalSE pups. SalEE pups increased the time spent in fast swim, slow swim, and diving, and decreased the time spent in struggling and immobility during the two sessions compared with SalSE pups. CocEE animals spent more time in fast swim and struggling and less the time in immobility compared with CocSE pups. The present results suggest that postnatal cocaine exposure affects the ability of these animals to cope with stressful situations, and that environmental enrichment seems to enable the rats to adopt a more active strategy, one that allows them to better cope with this particular stress situation.
- Effects of neonatal exposure to methamphetamine: Catecholamine levels in brain areas of the developing ratPublication . Silva, Joana Gomes da; Miguel, Rosário de; Fernández-Ruiz, Javier; Summavielle, Teresa; Tavares, M. Amélia; Summavielle, TeresaNeonatal exposure to moderate doses of methamphetamine during the first month of life in the rat affects tyrosine hydroxylase gene expression in the substantia nigra and nigrostriatal tyrosine hydroxylase activity. The main goal of this work was to evaluate the ontogeny of the neurochemical effects of repeated exposure to moderate doses of methamphetamine during the first month of life in the rat. Norepinephrine, dopamine, and dihydroxyphenylacetic acid levels were measured in target areas of methamphetamine: the substantia nigra, ventral tegmental area, caudate-putamen, nucleus accumbens, and medial prefrontal cortex. On postnatal day 1 (PND1), Wistar rat litters, culled to eight pups, sex balanced, were randomly attributed to either methamphetamine or control groups. Methamphetamine groups were administered 10 mg of (±)-methamphetamine/kg body weight/day, subcutaneously, from PND1 until the day prior to sacrifice; control groups received isovolumetric saline. Groups were sacrificed on PND7, PND14, and PND30. Neonatal methamphetamine exposure increased norepinephrine levels in the substantia nigra of PND30 rats; on PND14, this variation was evident only in male pups. In the substantia nigra, the dihydroxyphenylacetic/dopamine ratio was also affected in PND30 males. In the ventral tegmental area, catecholamine levels were not affected by methamphetamine. Norepinephrine levels were also increased in the caudate-putamen of PND7 male and PND14 female methamphetamine-exposed pups and in the nucleus accumbens of PND14 female and PND30 male and female pups. Catecholamine levels in the medial prefrontal cortex were not affected by neonatal methamphetamine administration.
- Prenatal cocaine exposure: effects on locomotor activity in rat offspringPublication . Magalhães, Ana; Summavielle, Teresa; Melo, Pedro; Tavares, Maria Amélia; Sousa, Liliana de; Summavielle, TeresaThis study examines the developmental effects of prenatal exposure to cocaine in the rat, evaluated during the first month of life through open-field behavior. The offspring of Wistar dams that received 60 mg/kg of cocaine, from gestational day 8 to 22, were examined in the open-field during the second, third and fourth weeks of postnatal life in three consecutive 15-min daily sessions, starting on postnatal day (PND) 14, (PND 14–16), PND 21 (PND 21–23) and PND 28 (PND 28–30). Results show that prenatal exposure to cocaine increased total activity and rearing behavior on PND 22 and PND 29. Also, on PND 14, cocaine-exposed animals reared significantly more than control rats. There were no significant differences in the frequency of center and peripheral ambulation, nor in the defecation rate. The present results evidence alterations in the emotional behavior of rats prenatally exposed to cocaine. The delayed onset of exploration in the open-field observed in cocaine-exposed animals suggests that they take more time to become habituated to a novel and open environment.
- IL-10 and Cdc42 modulate astrocyte-mediated microglia activation in methamphetamine-induced neuroinflammationPublication . Silva, Ana Isabel; Socodato, Renato; Pinto, Carolina; Terceiro, Ana Filipa; Canedo, Teresa; Relvas, João Bettencourt; Saraiva, Margarida; Summavielle, TeresaMethamphetamine (Meth) use is known to induce complex neuroinflammatory responses, particularly involving astrocytes and microglia. Building upon our previous research, which demonstrated that Meth stimulates astrocytes to release tumor necrosis factor (TNF) and glutamate, leading to microglial activation, this study investigates the role of the anti-inflammatory cytokine interleukin-10 (IL-10) in this process. Our findings reveal that the presence of recombinant IL-10 (rIL-10) counteracts Meth-induced excessive glutamate release in astrocyte cultures, which significantly reduces microglial activation. This reduction is associated with the modulation of astrocytic intracellular calcium (Ca2+) dynamics, particularly by restricting the release of Ca2+ from the endoplasmic reticulum to the cytoplasm. Furthermore, we identify the small Rho GTPase Cdc42 as a crucial intermediary in the astrocyte-to-microglia communication pathway under Meth exposure. By employing a transgenic mouse model that overexpresses IL-10 (pMT-10), we also demonstrate in vivo that IL-10 prevents Meth-induced neuroinflammation. These findings not only enhance our understanding of Meth-related neuroinflammatory mechanisms, but also suggest IL-10 and Cdc42 as putative therapeutic targets for treating Meth-induced neuroinflammation.
- Abnormal immunoreactivity to serotonin in cerebellar purkinje cells after neonatal cocaine exposurePublication . Summavielle, Teresa; Alves, Cecília J.; Monteiro, Pedro; Tavares, Maria AméliaNeonatal cocaine is known to affect the developing serotonergic system in many brain structures, including the cerebellum. Changes in the cerebellar Purkinje cells after drug exposure are well documented and result in impairment of movement and other cerebellar disorders such as ataxia. These cells have a major postnatal developmental pattern; therefore, neonatal exposure to cocaine is likely to affect them. In this work, male and female Wistar rats were injected with 15 mg of cocaine hydrochloride/kg body weight/day, subcutaneously, in two daily doses, from postnatal day 1 (PND1) to PND29. Controls were given 0.9% of saline. On PND14, PND21, and PND30, rats were transcardially perfused, and brains removed and cryoprotected. Coronal sections from the cerebellum were processed for immunocytochemistry of cells containing serotonin (5-hydroxytryptamine, or 5-HT). At the same postnatal age, rats from at least three different litters were sacrificed by decapitation, and brains were dissected for determination of 5-HT in the cerebellum by high-performance liquid chromatography with electrochemical detection. Upon the expected distribution of immunoreactivity to 5-HT, an abnormal immunoreactivity to 5-HT was observed in the Purkinje cells of six cocaineexposed animals, but not in control animals. Also, levels of cerebellar 5-HT in cocaine-exposed rats were significantly increased on PND21. These results, together with previously reported observations of altered patterns of motor behavior, indicate that neonatal cocaine exposure affects the serotonergic cerebellar system, altering the standard development of Purkinje cells and possibly compromising the motor function.
- Interlimb coordination during double support phase of gait in people with and without strokePublication . Couto, Ana G. B.; Vaz, Mário A. P.; Pinho, Liliana; Félix, José; Moreira, Juliana; Pinho, Francisco; Mesquita, Inês; Mesquita Montes, António; Crasto, Carlos; Sousa, AndreiaThis study aims to identify differences between participants with and without stroke regarding the ipsilesional and contralesional lower limbs kinematics, kinetics, muscle activity and their variability during double support phase of gait. Eleven post-stroke and thirteen healthy participants performed 10 gait trials at a self-selected speed while being monitored by an optoelectronic motion capture system, two force plates and an electromyographic system. The following outcomes were evaluated during the double support: the time and the joint position; the external mechanical work on the centre of mass; and the relative electromyographic activity. Both, contralesional/ipsilesional and dominant/non-dominant of participants with and without stroke, respectively, were evaluated during double support phase of gait in trailing or leading positions. The average value of each parameter and the coefficient of variation of the 10 trials were analysed. Post-stroke participants present bilateral decreased mechanical work on the centre of mass and increased variability, decreased contralesional knee and ankle flexion in trailing position, increased ipsilesional knee flexion in leading position and increased variability. Increased relative muscle activity was observed in post-stroke participants with decreased variability. Mechanical work on the centre of mass seems to be the most relevant parameter to identify interlimb coordination impairments in post-stroke subjects.