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31.
Anxiety disorders are among the most common mental disorders. Drugs that are often administered to manage medical problems cause rebound anxiety. The use of morphine and tramadol has increased in recent decades. In the present study, the effects of morphine and tramadol exposure during the neonatal and prepubertal periods on anxiety‐like behaviours in prepubertal rats were investigated. Male neonate rats were injected subcutaneously with saline, morphine or tramadol (3–21 mg/kg) on a daily basis from postnatal Day (P) 8 to P14. On P22, rats were divided into seven groups (saline/saline, saline/tramadol, saline/morphine, tramadol/saline, tramadol/tramadol, morphine/saline and morphine/morphine) and were injected with saline, tramadol or morphine for seven consecutive days. All rats were tested in an elevated plus maze (EPM) on P24 (acute effects), P27 (chronic effects) and P29. Locomotor activity was increased by the second and third exposure to the EPM. Re‐exposure to chronic morphine and tramadol resulted in increased locomotor activity, whereas acute and chronic administration of these drugs induced no notable difference. Anxiety decreased markedly after re‐exposure to tramadol and this anxiolytic‐like behaviour was more dominant in EPM re‐exposure in rats that had received higher doses of tramadol. Re‐exposure to tramadol elicited a stronger anxiolytic‐like behaviour than re‐exposure to morphine. It can be concluded that repeated morphine and tramadol administration during the neonatal period followed by re‐exposure to these drugs at an immature stage produces considerable anxiolytic‐like behaviour. Exposure to chronic morphine and tramadol during the neonatal period may affect the developing brain, which may induce long‐term changes in the opioid response.  相似文献   
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33.
Albumin is used as a plasma expander in critically ill patients and for several other clinical applications mainly via intravenous infusion. Oral administration of albumin can improve patient compliance although limited oral bioavailability of proteins is still a major challenge. Although nanomaterials have been extensively utilized for improving oral delivery of proteins, albumin has been utilized only as either a model drug or as a carrier for drug delivery. In the current study, for the first time, chitosan nanoparticles have been developed and extensively optimized to improve oral bioavailability of albumin as a therapeutic protein. Several characterizations have been performed for the albumin-loaded nanoparticles (e.g. drug encapsulation efficiency, DSC, FTIR, particle size, zeta potential, morphology, release kinetics, and enzymatic stability). Nanosized spherical particles were prepared and demonstrated high stability over three months either in a powdered form or as suspensions. Sustained release of albumin over time and high enzymatic stability as compared to the free albumin were observed. In vivo, higher serum concentrations of albumin in normal rabbits and cirrhotic rats were attained following oral and intraperitoneal administrations of the albumin-loaded nanoparticles as compared to the free albumin. The nanoparticles developed in the current study might provide efficient nanovehicles for oral administration of therapeutic albumin.  相似文献   
34.
Every year, millions of patients worldwide undergo cognitive testing. Unfortunately, new barriers to the use of free open access cognitive screening tools have arisen over time, making accessibility of tools unstable. This article is in follow-up to an editorial discussing alternative cognitive screening tools for those who cannot afford the costs of the Mini-Mental State Examination and Montreal Cognitive Assessment (see www.dementiascreen.ca ). The current article outlines an emerging disruptive “free-to-fee” cycle where free open access cognitive screening tools are integrated into clinical practice and guidelines, where fees are then levied for the use of the tools, resulting in clinicians moving on to other tools. This article provides recommendations on means to break this cycle, including the development of tool kits of valid cognitive screening tools that authors have contracted not to charge for (i.e., have agreed to keep free open access). The PRACTICAL.1 Criteria ( PRACTI cing C linician A ccessibility and L ogistical Criteria Version 1 ) are introduced to help clinicians select from validated cognitive screening tools, considering barriers and facilitators, such as whether the cognitive screening tools are easy to score and free of cost. It is suggested that future systematic reviews embed the PRACTICAL.1 criteria, or refined future versions, as part of the standard of review. Methodological issues, the need for open access training to insure proper use of cognitive screening tools, and the need to anticipate growing ethnolinguistic diversity by developing tools that are less sensitive to educational, cultural, and linguistic bias are discussed in this opinion piece. J Am Geriatr Soc 68:2207–2213, 2020.  相似文献   
35.
Memory for odour information may result from temporal coupling between the olfactory and hippocampal systems. Respiration defines the frequency of olfactory perception, but how the respiratory rate affects hippocampal oscillations remains poorly understood. The afferent connectivity of the medial septum/diagonal band of Broca complex (MS/DB) proposes this region as a crossroads between respiratory and limbic pathways. Here we investigate if the firing rates of septal neurons integrate respiratory rate signals. We demonstrate that approximately 50% of MS/DB neurons are temporally correlated with sniffing frequency. Moreover, a group of slow‐spiking septal neurons are phase‐locked to the sniffing cycle. We show that inter‐burst intervals of MS/DB theta cells relate to the sniff rate. Intranasal odour infusion evokes sniff phase preference for the activity of fast‐spiking MS/DB neurons. Concurrently, the infusion augments the correlation between sniffing and limbic theta oscillations. During periods of sniffing–theta correlation, CA1 place cells fired preferentially during the inhalation phase, suggesting the theta cycle as a coherent time frame for central olfactory processing. Furthermore, injection of the GABAergic agonist muscimol into medial septum induces a parallel decrease of sniffing and theta frequencies. Our findings provide experimental evidence that MS/DB does not merely generate theta rhythm, but actively integrates sensorimotor stimuli that reflect sniffing rate. Such integration may provide temporal oscillatory synchronisation of MS/DB‐innervated limbic structures with the sniffing cycle.  相似文献   
36.

Aim

Gender differences among homeless people may affect the frequency of their risky behaviours. This study was conducted to evaluate the behaviour patterns of homeless men and women in Tehran and compare the probable differences.

Subject and methods

In this study, 593 homeless people were recruited from five centres that house homeless people in Tehran, the capital city of Iran. A researcher-designed questionnaire was used to study behavioural patterns.

Results

In this study, homeless people (513 males and 80 females, all Iranian nationals) were enrolled in the study from June to August 2012. Mean age and mean duration of homelessness among women (35.46 and 12.68 months) were lower than those among men (42.74 and 56.85 months) (p?=?0.001). Although lifetime history of incarceration in men was higher than in women (p?=?0.002), mean duration of imprisonment in the last 10 years in men (21.25 months) and women (17.76 months) was not statistically different (p?=?0.07). Accommodation locality in the past 6 months varied between men and women. Women were current drug users more often than men were (61.53 % versus 45.26 %) (p?=?0.02). The type of drug consumption in women (methamphetamine) differed from that of men (opium and heroin). More men had a history of injecting drugs than did women (30.02 % versus 12.30 %) (p?=?0.003). Condom use at the last sexual encounter was reported to be higher in women compared to men (74.60 % versus 26.62 %) (p?=?0.001).

Conclusion

This study showed notable differences in behaviour patterns between homeless men and women and also indicated that homeless people in Tehran exhibit many risky behaviours.  相似文献   
37.
We investigated the biological response of human pluripotent stem cells (hPSCs) cultured on a carbon nanotube (CNT) array-based substrate with the long term goal to direct hPSC germ layer specification for a wide variety of tissue engineering applications. CNT arrays were fabricated using a chemical vapor deposition system allowing for control over surface roughness and mechanical stiffness. Our results demonstrated that hPSCs readily attach to hydrophilized and extracellular matrix coated CNT arrays. hPSCs cultured as colonies in conditions supporting self-renewal demonstrated the morphology and marker expression of undifferentiated hPSCs. Conditions inducing spontaneous differentiation lead to hPSC commitment to all three embryonic germ layers as assessed by immunostaining and RT-PCR analysis. Strikingly, the physical characteristics of CNT arrays favored mesodermal specification of hPSCs. This is contradictory to the behavior of hPSCs on traditional tissue culture plastic which promotes the development of ectoderm. Altogether, these results demonstrate the potential of CNT arrays to be used in the generation of new platforms that allow for precise control of hPSC differentiation by tuning the characteristics of their physical microenvironment.  相似文献   
38.
Using 3D models of bones can highly improve accuracy and reliability of orthopaedic evaluation. However, it may impose excessive computational load. This article proposes a fully automatic method for extracting a compact model of the femur from its 3D model. The proposed method works by extracting a 3D skeleton based on the clinical parameters of the femur. Therefore, in addition to summarizing a 3D model of the bone, the extracted skeleton would preserve important clinical and anatomical information. The proposed method has been applied on 3D models of 10 femurs and the results have been evaluated for different resolutions of data.  相似文献   
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40.
Pemphigus vulgaris (PV) is a chronic autoimmune disorder with potentially fatal outcomes. The aim of this study was to investigate the effect of l ‐carnitine (LC) on secreted frizzled‐related protein‐5 (SFRP5), omentin, visfatin, and glycemic indices in PV patients under corticosteroid treatment. In this randomized, double‐blind, placebo‐controlled clinical trial, 52 patients with PV were divided randomly into two groups to receive 2 g of LC or a placebo for 8 weeks. Serum levels of SFRP5, omentin, visfatin, and also glycemic indices were evaluated at the baseline and end of the study. LC supplementation significantly decreased the serum level of visfatin (95% CI [?14.718, ?0.877], p = .05) and increased the serum levels of SFRP5 (95%CI [1.637, 11.380], p < .006) and omentin (95% CI [9.014, 65.286], p < .01). However, LC supplementation had no significant effects on the serum levels of glycemic factors such as insulin (95% CI [?1.125, 3.056], p = .426), fasting blood sugar (95% CI [?4.743, 3.642], p = .894), homeostatic model assessment of insulin resistance (95% CI [?0.305, 0.528], p = .729), and quantitative insulin‐sensitivity check index (95% CI [?0.016, ?0.010], p = .81). LC supplementation decreased visfatin serum level and increased omentin‐1 and SFRP5 serum levels in patients with PV. However, it has no significant effect on the serum levels of insulin and glycemic indices.  相似文献   
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