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61.

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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The objective of the present study was to examine the relationships between infertility characteristics, cognitive coping strategies, and depressive symptoms in definitive involuntarily childless people. Both cross-sectional and prospective relationships were studied in a sample of 169 persons for whom an involuntarily childless future was definitive. The Cognitive Emotion Regulation Questionnaire (CERQ) and the Symptom Check List (SCL-90) were filled out at home. Almost no infertility characteristics were related to depressive symptoms. The cognitive coping strategies self-blame, rumination, catastrophizing and positive reappraisal appeared to be related to depressive symptoms. In addition, catastrophizing was related to depressive symptoms two years later. These findings suggest that intervention programs for people with definitive involuntary childlessness should pay attention to cognitive coping strategies.  相似文献   
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Chen CP  Chang SC  Vivian Yang WC 《Placenta》2007,28(2-3):97-106
Impaired glucose metabolism with diabetes may alter the expressions of proteoglycans (PGs), which may impair the biological functions of placenta. In this study, we investigated the expression of PGs and their conjugated glycosaminoglycan (GAG) composition in the placentas of mothers with gestational diabetes mellitus (GDM) and trophoblasts cultured in a high-glucose condition. The PGs by guanidine/HCl extraction and DEAE Sepharose fractionation followed by GAG degradation enzyme digestion analyses showed that the expression of chondroitin sulfate and/or dermatan sulfate (CS/DS) PGs was increased whereas the heparan sulfate (HS) PG was decreased in GDM placentas compared to controls. Western blot analyses demonstrated that the increased CS/DS PGs in GDM placentas were predominantly the small leucine-rich proteoglycans (SLRPs), decorin and biglycan. Increased mRNA expression level was consistently shown by quantitative real-time PCR. Immunohistochemistry indicated intensive staining of decorin and biglycan in the diabetic placenta with different localizations. Additionally, the basement membrane HSPG, perlecan was found to contain both CS/DS and HS in GDM placentas and plain HS in controls. Similar findings of PG alterations induced by hyperglycemia were observed in cultured trophoblast in a high-glucose condition. This study demonstrated that hyperglycemia induced not only the gene expressions of PGs but also alterations in the carried GAG type and composition.  相似文献   
66.
ObjectiveTo explore the perspectives and preferences of pregnant women receiving prenatal care in a rural community regarding delivery location.DesignExploratory qualitative research project.SettingThe La Ronge Medical Clinic in northern Saskatchewan.ParticipantsPregnant women of any parity aged 18 years or older who attended the clinic for prenatal care from March 1, 2018, to March 31, 2019, were invited to participate. The closest obstetric and surgical services are 240 km away.MethodsThis project was undertaken using semistructured interviews. The interviews were audiorecorded, transcribed, and analyzed using an inductive thematic analysis, taking into consideration both saturation and analyst triangulation. The investigators and researchers on this project were family medicine residents and faculty in a remote medical clinic.Main findingsThe factors that played a substantial role in influencing the patients’ decisions regarding delivery location included access to medical services, proximity to home community, perceptions of medical care providers, and some unique features of local hospitals. The participants largely believed they maintained their autonomy in selecting their preferred delivery location while seeking input from their prenatal care providers and families.ConclusionPregnant women in this rural community consider many factors when deciding on their delivery location. These findings can be taken into consideration by physicians when discussing with their rural patients the risks and benefits of delivery in both rural and urban centres. Barriers to local delivery should be addressed, while maintaining a woman’s autonomy to choose where she gives birth.  相似文献   
67.
ObjectiveThe aim of this study was to assess the nutritional zinc (Zn) status of elite swimmers during different training periods.MethodsA longitudinal paired study was performed at the University of Sao Paulo in eight male swimmers 18 to 25 y old who had been swimming competitively at the state and national levels for at least 5 y. The swimmers were evaluated over a total period of 14 wk: before the basic and specific preparatory period (BSPP-baseline), at the end of the basic and specific preparatory period (post-BSPP), and at the end of the polishing period (PP). Levels of Zn were determined in the plasma, erythrocyte, urine, and saliva by atomic absorption spectrophotometry. Anthropometric measurements and a 3-d food record were also evaluated.ResultsThe median plasma Zn concentration was below the reference value in all training periods (BSPP-baseline 59 μg/dL, post-BSPP 55.9 μg/dL, after PP 58.8 μg/dL, P > 0.05), as were threshold values for erythrocytes (BSPP-baseline 36.5 μg of Zn/g of hemoglobin, post-BSPP 42 μg of Zn/g of hemoglobin, after PP 40.7 μg of Zn/g of hemoglobin, P > 0.05), urinary Zn (BSPP-baseline 280 μg/24 h, post-BSPP 337 μg/24 h, after PP 284 μg/24 h, P > 0.05), and salivary Zn (BSPP-baseline 66.1 μg/L, post-BSPP 54.1 μg/L, after PP 79.7 μg/L, P > 0.05). Salivary Zn did not correlate with plasma and erythrocyte Zn levels.ConclusionThe results suggest that the elite swimmers studied presented a possible Zn deficiency and that salivary Zn was not adequate to evaluate the Zn nutritional status.  相似文献   
68.
The permanent ice cover of Lake Vida (Antarctica) encapsulates an extreme cryogenic brine ecosystem (−13 °C; salinity, 200). This aphotic ecosystem is anoxic and consists of a slightly acidic (pH 6.2) sodium chloride-dominated brine. Expeditions in 2005 and 2010 were conducted to investigate the biogeochemistry of Lake Vida’s brine system. A phylogenetically diverse and metabolically active Bacteria dominated microbial assemblage was observed in the brine. These bacteria live under very high levels of reduced metals, ammonia, molecular hydrogen (H2), and dissolved organic carbon, as well as high concentrations of oxidized species of nitrogen (i.e., supersaturated nitrous oxide and ∼1 mmol⋅L−1 nitrate) and sulfur (as sulfate). The existence of this system, with active biota, and a suite of reduced as well as oxidized compounds, is unusual given the millennial scale of its isolation from external sources of energy. The geochemistry of the brine suggests that abiotic brine-rock reactions may occur in this system and that the rich sources of dissolved electron acceptors prevent sulfate reduction and methanogenesis from being energetically favorable. The discovery of this ecosystem and the in situ biotic and abiotic processes occurring at low temperature provides a tractable system to study habitability of isolated terrestrial cryoenvironments (e.g., permafrost cryopegs and subglacial ecosystems), and is a potential analog for habitats on other icy worlds where water-rock reactions may cooccur with saline deposits and subsurface oceans.  相似文献   
69.
Objective: To evaluate the influence of the local prenatal surveillance of twin pregnancies in the obstetrical results.

Methods: A prospective cohort study of multiple pregnancies delivered over a period of 16 years in a tertiary centre was conducted. In this study 861 twin pregnancies were included. They were compared for obstetric complications, gestational age at delivery, mode of delivery and birthweight, according to the place of the surveillance.

Results: Of the 861 cases examined, the following obstetric complications were significantly different: metrorrhagia (p?=?0.039), infections (p?p?=?0.007), PROMPT (p?p?=?0.024). The mode of delivery was similar but occurred mostly ≤32 weeks (p?p?Conclusion: Our results demonstrate the crucial importance of prenatal surveillance be carried in a differentiated referral centers with specific/strict protocols or the urgent implementation of same protocols in all other places of surveillance, since this straight surveillance greatly reduces the occurrence of prenatal complications, mainly PROMPT, PTD.  相似文献   
70.
Angiotensin II inhibits insulin-induced activation of phosphatidylinositol 3-kinase through a mechanism, at least in part, dependent on serine phosphorylation of the insulin receptor and insulin receptor substrates (IRS)-1/2. Recent evidence shows that suppressor of cytokine signaling-3 (SOCS-3) is induced by insulin and angiotensin II and participates in the negative control of further stimulation of each of these signaling systems independently. In the present study, we evaluated the interaction of angiotensin II-induced SOCS-3 with the insulin signaling pathway in the heart of living rats. A single iv dose of angiotensin II promotes a significant increase of SOCS-3 in heart, an effect that lasts up to 180 min. Once induced, SOCS-3 interacts with the insulin receptor, JAK-2, IRS-1, and IRS-2. The inhibition of SOCS-3 expression by a phosphorthioate-modified antisense oligonucleotide partially restores angiotensin II-induced inhibition of insulin-induced insulin receptor, IRS-1 and IRS-2 tyrosine phosphorylation, and IRS-1 and IRS-2 association with p85-phosphatidylinositol 3-kinase and [Ser473] phosphorylation of Akt. Moreover, the inhibition of SOCS-3 expression partially reverses angiotensin II-induced inhibition of insulin-stimulated glucose transporter-4 translocation to the cell membrane. These results are reproduced in isolated cardiomyocytes. Thus, SOCS-3 participates, as a late event, in the negative cross-talk between angiotensin II and insulin, producing an inhibitory effect on insulin-induced glucose transporter-4 translocation.  相似文献   
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