Experimental studies on the long-term effects of methylphenidate hydrochloride

Toxicology ◽  
1995 ◽  
Vol 103 (2) ◽  
pp. 77-84 ◽  
Author(s):  
June K. Dunnick ◽  
James R. Hailey
1995 ◽  
Vol 2 (3) ◽  
pp. 279 ◽  
Author(s):  
Max Abensperg-Traun ◽  
Dion Steven ◽  
Lyn Atkins

The harvester termites in floristically rich mallee-heath of southern Western Australia appear resilient to high-intensity fire. This contrasts with the temporary extinction of harvesters occupying a narrow food niche in floristically simple, intensely burnt spinifex Triodia angusta grassland in tropical Western Australia. The present study examines the effects of high-intensity fire on harvester termites Drepanotermes tamminensis in vegetation of intermediate floristic diversity and compares its findings with these earlier studies. We sampled 20 mounds (termitaria) in both an unburnt and (adjacent) burnt stand of Allocasuarina campestris shrubland. Although partially regenerated three years after the fire, 40% of mounds in the burnt area were abandoned, contrasting with 10% in the unburnt stand. No harvested chaff was found in any of the abandoned mounds. The extent of mound occupation by D. tamminensis was considerably lower, and ant invasion higher, in the burnt stand. These findings are consistent with the hypothesis that high floristic diversity enhances the resilience of harvester termites to fire. The most likely mechanism is the availability of a range of plant (food) species with different regenerative responses to high-intensity fire. The death of spinifex and the associated harvester termites after fire may be atypical. We argue, however, that temporary extinction of harvester populations in arid Australia may not be exceptional, particularly where fire coincides with drought and high livestock grazing pressure. Rigorous experimental studies are necessary to enhance our understanding of the long-term effects of fire on harvester termite populations in different vegetation types and climatic zones.


2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Deborah M. Sloboda ◽  
Minglan Li ◽  
Rachna Patel ◽  
Zoe E. Clayton ◽  
Cassandra Yap ◽  
...  

The consumption of artificially sweetened processed foods, particularly high in fructose or high fructose corn syrup, has increased significantly in the past few decades. As such, interest into the long term outcomes of consuming high levels of fructose has increased significantly, particularly when the exposure is early in life. Epidemiological and experimental evidence has linked fructose consumption to the metabolic syndrome and associated comorbidities—implicating fructose as a potential factor in the obesity epidemic. Yet, despite the widespread consumption of fructose-containing foods and beverages and the rising incidence of maternal obesity, little attention has been paid to the possible adverse effects of maternal fructose consumption on the developing fetus and long term effects on offspring. In this paper we review studies investigating the effects of fructose intake on metabolic outcomes in both mother and offspring using human and experimental studies.


2021 ◽  
Vol 31 (3) ◽  
pp. 529-536
Author(s):  
Bogdan PAVEL ◽  
◽  
Mihaela Roxana POPESCU ◽  
Carmen-Denise-Mihaela ZAHIU ◽  
Patricia Demetria POPOVICI ◽  
...  

Heart rate variability (HRV) has long been associated with cardiovascular risk, especially after a myocardial infarction, but also in general. HRV refl ects and is used as a surrogate for the balance between sympathetic and parasympathetic systems in modulating the cardiovascular activity. A low HRV, traditionally associated to sympathovagal imbalance, is associated with a worse cardiovascular prognosis. Deep brain stimulation (DBS) is a surgical technique used for severe cases of Parkinson’s disease and other neurologic pathologies. DBS is performed in various areas of the brain and through different protocols. The claustrum, an area located between the external capsule and the insular cortex, was recently shown to be connected to Parkinson’s motor symptoms. As DBS in other regions of the brain has proven non-motor effects, like infl uencing the HRV, we sought to document the effect of claustrum stimulation on the sympatho-vagal balance (SVB). Our preliminary data indicates that claustrum stimulation inclines the SVB toward the latter, but more studies are required to observe the long-term effects of this type of stimulation.


2015 ◽  
Vol 308 (8) ◽  
pp. F824-F831 ◽  
Author(s):  
Tsjitske J. Toering ◽  
Anne Marijn van der Graaf ◽  
Folkert W. Visser ◽  
Henk Groen ◽  
Marijke M. Faas ◽  
...  

Formerly preeclamptic women have an increased risk for developing end-stage renal disease, which has been attributed to altered renal hemodynamics and abnormalities in the renin-angiotensin-aldosterone system. Whether this is due to preeclampsia itself or to comorbid conditions is unknown. Renal hemodynamics and responsiveness to ANG II during low Na+ intake (7 days, 50 mmol Na+/24 h) and high Na+ (HS) intake (7 days, 200 mmol Na+/24 h) were studied in 18 healthy normotensive formerly early-onset preeclamptic women (fPE women) and 18 healthy control subjects (fHP women), all selected for absence of comorbidity. At the end of each diet, renal hemodynamics and blood pressure were measured before and during graded ANG II infusion. Both HS intake and former preeclampsia increased filtration fraction (FF) without an interaction between the two. FF was highest during HS intake in fPE women [0.31 ± 0.12 vs. 0.29 ± 0.11 in fHP women, generalized estimating equation analysis (body mass index corrected), P = 0.03]. The renal response to ANG II infusion was not different between groups. In conclusion, fPE women have a higher FF compared with fHP women. As this was observed in the absence of comorbidity, preeclampsia itself might exert long-term effects on renal hemodynamics. However, we cannot exclude the presence of prepregnancy alterations in renal function, which, in itself, lead to an increased risk for preeclampsia. In experimental studies, an elevated FF has been shown to play a pathogenic role in the development of hypertension and renal damage. Future studies, however, should evaluate whether the subtle differences in renal hemodynamics after preeclampsia contribute to the increased long-term renal risk after preeclampsia.


2018 ◽  
Vol 89 (5) ◽  
pp. 362-371 ◽  
Author(s):  
Svetlana Lajic ◽  
Leif Karlsson ◽  
Anna Nordenström

Prenatal treatment of congenital adrenal hyperplasia with dexamethasone (DEX) has been in use since the mid-1980s and has proven effective at reducing virilization of external genitalia in affected girls. However, multiple experimental studies on animals and clinical studies on humans show that prenatal administration of glucocorticoids may cause unwanted adverse effects which have raised concerns about the long-term safety of the treatment. The long-term outcome of prenatal DEX treatment on cognition has been investigated, but the results are still conflicting. Overall, most of the evidence points towards a negative effect on executive functions where girls seem to be more susceptible than boys. Some effects on social behavior have been observed, but results are still contradictory and treated children are mostly well adapted. Cardiovascular, renal, and metabolic function are still areas to be investigated. Larger studies are warranted to investigate areas other than cognition and behavior and to be able to draw more definitive conclusions about prenatal DEX treatment.


1980 ◽  
Vol 162 (4) ◽  
pp. 23-33 ◽  
Author(s):  
James F. Christie

This review focuses on research studies that have investigated the effects of play on children's cognitive growth. Three groups of investigations are reviewed: (1) correlational studies, (2) experimental studies, and (3) play-training studies. The results of these investigations indicate that play and play training can result in short-term improvements in divergent thinking, problem-solving ability, verbal intelligence, and several other cognitive performance variables. The educational implications of these findings are discussed. The review concludes by pointing out the need for longitudinal research to assess the long-term effects of play on children's cognitive growth and academic achievement.


1986 ◽  
Vol 20 (2) ◽  
pp. 148-154
Author(s):  
J. A. Schouten ◽  
A. C. Beynen ◽  
P. D. de Rooy ◽  
H. F. W. Hoitsma ◽  
A. Bosma

Partial ileal bypass (PIB) surgery is a method for the treatment of familial hypercholesterolaemia in man. Since the rabbit is frequently used as an animal model in experimental studies on PIB, we have investigated the long-term effects of this surgical procedure on the health status of rabbits. Forty-eight weeks after surgery plasma and liver cholesterol levels were decreased by about 40%. The inner diameter of the bypassed ileum was drastically reduced, unlike its length. The bypassed segment did not show clear histological abnormalities. The microflora of the caecum was similar in control and PIB rabbits. PIB did not influence liver histology. The bile of the rabbits with PIB was less lithogenic than that of control animals. Blood haemoglobin levels, haematocrit values and plasma concentrations of alkaline phosphatase, alanine aminotransferase, γ-glutamyl transferase and lactate dehydrogenase were not changed after PIB. Plasma levels of albumin, creatinine, calcium, phosphorus, vitamin B12 and folic acid were not significantly affected by PIB. Rabbits with PIB had significantly higher plasma levels of bilirubin and zinc than control rabbits, but plasma vitamin E concentrations were significantly lower. These results may be of importance for further studies on the effects of PIB in rabbits.


2018 ◽  
Vol 833 ◽  
pp. 298-306 ◽  
Author(s):  
Manuella da L.D. Barros ◽  
Raul Manhães-de-Castro ◽  
Daniele T. Alves ◽  
Omar Guzmán Quevedo ◽  
Ana Elisa Toscano ◽  
...  

2018 ◽  
Vol 5 (4) ◽  
pp. 81-98 ◽  
Author(s):  
Christian Nyman Gomez ◽  
Björn Berg Marklund

This paper studies whether a board game can effectively raise awareness of cultural differences and their impacts on everyday life. Furthermore, the paper compares whether a board game might achieve this goal more efficiently, or differently, than more traditional ‘open discussion’ exercises. To conduct this study, a board game that present players with cultural dilemmas was designed and developed based on a comparative model of individualistic and collectivistic cultures. The game’s ability to generate discussion and engagement with cross-cultural topics was evaluated and compared with traditional discussion exercises in a series of experimental studies conducted in SFI (Swedish For Immigrants) classrooms. A follow-up survey was also conducted to compare long-term effects between the board game and the traditional discussion exercise. Results indicate that the game benefited participants’ discussions and reflections regarding cultural awareness directly after the game session, and that they retained their attitudes and perceptions of cultural awareness better than participants of the non-game exercise.


2019 ◽  
pp. S207-S217
Author(s):  
S. MURDEN ◽  
V. BORBÉLYOVÁ ◽  
Z. LAŠTŮVKA ◽  
J. MYSLIVEČEK ◽  
J. OTÁHAL ◽  
...  

Hypoxic-ischemic encephalopathy (HIE) is a neonatal condition that occurs as a consequence of perinatal asphyxia, which is caused by a number of factors, commonly via compression of the umbilical cord, placental abruption, severe meconium aspiration, congenital cardiac or pulmonary anomalies and birth trauma. Experimental studies have confirmed that male rat pups show a higher resistance to HIE treatment. Moreover, the long-term consequences of hypoxia in male are more severe in comparison to female rat pups. These sex differences can be attributed to the pathophysiology of hypoxia-ischemia, whereby studies are beginning to establish such gender-specific distinctions. The current and sole treatment for HIE is hypothermia, in which a reduction in temperature prevents long-term effects, such as cerebral palsy or seizures. However, in most cases hypothermia is not a sufficient treatment as indicated by a high mortality rate. In the present review, we discuss the gender differences within the pathophysiology of hypoxia-ischemia and delve into the role of gender in the incidence, progression and severity of the disease. Furthermore, this may result in the development of potential novel treatment approaches for targeting and preventing the long-term consequences of HIE.


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