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A functional polymorphism in the regulatory region of the serotonin transporter gene (5-HTTLPR) is considered to be a plausible candidate gene for anxiety-related personality traits and for alcoholism. Empirical support for the association between 5-HTTLPR and psychological traits has been somewhat inconsistent; however, observations of the functional dominance of the low-activity s-allele over the l-allele have been more consistent. When studying the influence of particular genes on psychological traits, it seems useful also to assess more biological intermediate traits that may mediate the effects of those genes on the traits of interest. The present study examined relationships between 5-HTTLPR genotype, whole blood serotonin (5-HT) level, and platelet 5-HT binding in 150 Caucasian subjects from 50 biological families. Individuals with the s-allele had lower average platelet 5-HT binding availability than those with the l/l genotype (P<0.025). Whole blood 5-HT level was not associated with 5-HTTLPR genotype. In adult men, those with the s-allele had higher mean scores on the NEO-FFI personality trait of openness than did those with the l/l genotype (P=0.002). The effect was not statistically significant in women (P=0.42), although it was in the same direction. Our findings do not support an association of 5-HTTLPR genotype with alcoholism diagnosis, alcoholism subtype, or the personality trait of neuroticism. The results of this pilot study suggest that further work should examine the mediation of the genetic effects on personality traits by biochemical measures and their moderation by gender.  相似文献   
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In December 2019, a new viral respiratory infection known as coronavirus disease 2019 (COVID-19) was first diagnosed in the city of Wuhan, China. COVID-19 quickly spread across the world, leading the World Health Organization to declare it a pandemic on March 11, 2020. The disease is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a similar virus to those involved in other epidemics such as severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV). Epidemiological studies have shown that COVID-19 frequently affects young adults of reproductive age and that the elderly and patients with chronic disease have high mortality rates. Little is known about the impact of COVID-19 on pregnancy and breastfeeding. Most COVID-19 cases present with mild flu-like symptoms and only require treatment with symptomatic relief medications, whereas other cases with COVID-19 require treatment in an intensive care unit. There is currently no specific effective treatment for COVID-19. A large number of drugs are being used to fight infection by SARS-CoV-2. Experience with this therapeutic arsenal has been gained over the years in the treatment of other viral, autoimmune, parasitic, and bacterial diseases. Importantly, the search for an effective treatment for COVID-19 cannot expose pregnant women infected with SARS-CoV-2 to the potential teratogenic risks of these drugs. Therefore, it is necessary to determine and understand the safety of anti-COVID-19 therapies prior to conception and during pregnancy and breastfeeding.Key words: COVID-19, SARS-CoV-2, antiviral, pregnancy, breastfeeding  相似文献   
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The Melanotic Neuroectodermal Tumor of Infancy (MNTI) is an asymptomatic, pigmented neoplasm characterized by a fast and locally aggressive growth along with a rare tissue formation. In the diagnostic process, the use of imaging exams can suggest a local destruction suggestive of malignancy, a sign of bone remodeling and expansion. Therefore, as any early diagnosis minimizes risks and improves the prognosis of treatment for the patient, the aim of this study was, based on a clinical case report, to corroborate the use of histopathological analysis associated with immunohistochemistry. Thus, we conclude that the immunohistochemical exam is of great importance for a better complementation of the MNTI diagnosis process. In addition, it can reveal signs of possible aggressive growth.  相似文献   
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Ethnopharmacological relevance

Petiveria alliacea L. (tipi) a shrub from Phytolaccaceae family is popularly used in folk medicine for treating a wide variety of disorders in South and Central America.

Aim of the study

To investigate the neuropharmacological properties on experimental animals.

Materials and methods

The acetate (FA), hexanic (FH), hydroalcoholic (FHA) and precipitated hydroalcoholic (FHAppt) fractions from the root of tipi were studied to investigate its pharmacological properties in the classical behavioral models (open-field, elevated plus maze-EPM, rotarod, barbiturate-induced sleeping time, forced swimming and pentylenetetrazole (PTZ)-induced convulsions tests) using mice. These fractions were administered intraperitoneally and orally to female mice at single doses of 100 and 200 mg/kg.

Results

All these fractions decreased the locomotor activity, rearing and grooming in the open-field test, suggesting a possible central depressant action. No significant effect was evident on motor coordination of the animals in the rotarod test. On EPM, all the fractions of tipi presented a significant reduction on the time of permanence in the open arms, indicating an absence of anxiolytic-like effect. In addition, the fractions increased the immobility time in the forced swimming test and potentiated pentobarbital-induced sleeping time in mice, confirmed a probable sedative and central depressant effect. Furthermore, the fractions increased the latency to the first convulsion and the lethal time of the PTZ-induced convulsions test in the animals, confirmed its popular use as anticonvulsant.

Conclusion

Our results suggest that the fractions of P. alliacea L. contains biologically active substance(s) that might be acting in the CNS and have significant depressant and anticonvulsant potentials, supporting folk medicine use of this plant.  相似文献   
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Calculated therapeutic doses of digitalis did not produce a significant change in the coronary blood flow of the dog. This confirms the results of Essex, Herrick, Baldes, and Mann.28Calculated toxic doses of digitalis decreased the coronary blood flow of dogs four to six hours after the drug had been administered. The diminution of flow persisted for several days after a single toxic dose of the drug.No myocardial lesions were observed after a therapeutic dose of digitalis, nor were they observed in one animal which received a toxic dose of digitalis. In the latter animal the coronary blood flow returned to the preinjection level within two days.Myocardial lesions were observed in one animal in which the coronary blood flow was kept well below the control level for twelve days by repeated injections of digitalis (toxic range).The diminution of coronary blood flow after the injection of toxic doses of digitalis could not be correlated consistently with changes in the pulse rate or systemic blood pressure.After the injection of toxic doses of digitalis the coronary blood flow returned to the control level in several experiments, and the animals recovered completely.  相似文献   
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