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991.
To verify the possibility that the pedunculopontine nucleus is a source of glutamatergic terminals in contact with midbrain dopaminergic neurons in the squirrel monkey, we used the anterograde transport of Phaseolus vulgaris-leucoagglutinin in combination with preembedding immunohistochemistry for tyrosine hydroxylase and for calbindin D-28k and postembedding immunocytochemistry for glutamate and for γ-aminobutyric acid. Following tracer injections in the pedunculopontine nucleus, numerous anterogradely labeled fibers emerged from the injection sites to innervate densely the pars compacta of the substantia nigra and ventral tegmental area. The major type of labeled fibers were thin with multiple collaterals and varicosities that established intimate contacts with midbrain dopaminergic neurons. At the electron microscopic level, the anterogradely labeled boutons were medium sized (maximum diameter between 0.9 μm and 2.5 μm) and contained numerous round vesicles and mitochondria. Postembedding immunocytochemistry revealed that 40–60% of anterogradely labeled terminals were enriched in glutamate and formed asymmetric synapses with dendritic shafts of substantia nigra and ventral tegmental area neurons. In triple-immunostained sections, some of the postsynaptic targets to these terminals were found to be dopaminergic. In addition, 30–40% of the anterogradely labeled terminals in both regions displayed immunoreactivity for γ-aminobutyric acid and, in some cases, formed symmetric synapses with dendritic shafts. In conclusion, our results provide the first ultrastructural evidence for the existence of synaptic contacts between glutamate-enriched terminals from the pedunculopontine nucleus and midbrain dopaminergic neurons in primates. Our results also show that the pedunculopontine nucleus is a potential source of γ-aminobutyric acid input to this region. These findings suggest that the pedunculopontine nucleus may play an important role in the modulation of the activity of midbrain dopaminergic cells by releasing glutamate or γ-aminobutyric acid as neurotransmitter. © 1996 Wiley-Liss, Inc. 相似文献
992.
Tamara Searle Faisal R. Ali Sarah Carolides Firas Al-Niaimi 《The Journal of clinical and aesthetic dermatology》2021,14(12):49
ObjectiveRosacea is a common inflammatory cutaneous condition with a complex yet unknown etiopathogenesis. Diet and certain food items are known to trigger or worsen rosacea symptoms, but conflicting and often inconsistent advice is given to patients regarding this link. We provide an up-to-date literature review on the relationship between rosacea and diet.MethodsUsing the keywords “alcohol,” “diet,” “flushing,” “food,” “inflammation,” “rosacea,” “skin-gut axis” and “spice” we systemically searched the databases PubMed, MEDLINE and EMBASE for English-language articles in July 2020.ResultsThe most frequently reported triggers implicated in rosacea include alcohol, spicy food, cinnamaldehyde-containing foods (e.g., tomatoes, citrus fruits, chocolate), hot drinks, and histamine-rich foods (e.g., aged cheese, wine, processed meats). Some food items appear to play a protective role, such as omega-3, which appears to protect against ocular rosacea. The relationship between certain food items and the subtype of rosacea is varied, with inconsistent results shown in the few studies that examined this. As an example, alcohol worsens flushing and fatty food triggers both erythematotelangiectatatic and phymatous rosacea in susceptible individuals.ConclusionWhile several food types appear to be associated with exacerbation of rosacea, there are no recommendations that can be applied to all patients. Further studies are needed to examine the exact link between diet and rosacea subtypes. 相似文献
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994.
Jane Tiller Ulrike Schmidt Shireen Ali Janet Treasure 《The International journal of eating disorders》1995,17(4):365-371
The level and direction of hostility in patients with bulimia nervosa, anorexia nervosa and a comparison group were measured using the Hostility and Direction of Hostility Questionnaire. A semistructured interview developed by Harris, Brown, and Bifulco (Psychological Medicine, 16, 641-659, 1986) was used to assess childhood care to examine whether a link exists between childhood exposure to aggression or parental neglect and adult hostility. Patients with eating disorders had significantly higher hostility levels and were significantly more intropunitive than the comparison group. Patients with bulimia nervosa were significantly more intropunitive than the comparison group. Patients with bulimia nervosa were significantly more hostile than patients with anorexia nervosa. Anorexia nervosa patients were more likely to direct hostility inwardly, rather than outwardly, when compared with bulimia nervosa patients. Impulsivity was associated with extrapunitiveness whereas intropunitiveness was associated with depression. Although some measures of poor childhood care correlated with adult hostility levels no clear pattern emerged. © 1995 by John Wiley & Sons, Inc. 相似文献
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998.
Mehrnoosh Tavakoli Ali Ghasemian Mohammad Reza Dehghani-Firouzabadi Bartomiej Mazela 《Materials》2022,15(1)
The inevitable destructive effects of moisture and temperature are obvious in cellulosic and nanocellulosic substrates. These materials are the main foundations of interdependent industries that produce products such as currency notes or high-quality packaging for sanitary, cosmetics, or ammunition in the defense industry. Therefore, it is essential to develop procedures to eliminate problems arising from humidity and fire to improve the quality of these green and sustainable materials. The production of waterproof and flame-resistant cellulose-based substrates has drawn increasing attention to resolve these drawbacks. In this review paper, we have initially summarized the most accessible cellulosic substrates, different kinds of nanocellulose, and the general information about water repellents and intumescent fireproof surfaces. Then, the potential and necessity of using cellulosic biobased substrates are addressed for use in modified shapes as waterproof and fire inhibitor coatings. Cost-effective, eco-friendly, and durable, dual-function coatings are also introduced as future challenges, which are exploited as water-repellents and flame-retardant cellulose-based surfaces for pulp and paper applications. 相似文献
999.
Mohsin Ali Khan Furqan Farooq Mohammad Faisal Javed Adeel Zafar Krzysztof Adam Ostrowski Fahid Aslam Seweryn Malazdrewicz Mariusz Malak 《Materials》2022,15(1)
To avoid time-consuming, costly, and laborious experimental tests that require skilled personnel, an effort has been made to formulate the depth of wear of fly-ash concrete using a comparative study of machine learning techniques, namely random forest regression (RFR) and gene expression programming (GEP). A widespread database comprising 216 experimental records was constructed from available research. The database includes depth of wear as a response parameter and nine different explanatory variables, i.e., cement content, fly ash, water content, fine and coarse aggregate, plasticizer, air-entraining agent, age of concrete, and time of testing. The performance of the models was judged via statistical metrics. The GEP model gives better performance with R2 and ρ equals 0.9667 and 0.0501 respectively and meet with the external validation criterion suggested in the previous literature. The k-fold cross-validation also verifies the accurateness of the model by evaluating R2, RSE, MAE, and RMSE. The sensitivity analysis of GEP equation indicated that the time of testing is the influential parameter. The results of this research can help the designers, practitioners, and researchers to quickly estimate the depth of wear of fly-ash concrete thus shortening its ecological susceptibilities that push to sustainable and faster construction from the viewpoint of environmentally friendly waste management. 相似文献
1000.
Farnaz Sepandar Maryam Daneshpazhooh Mahmoud Djalali Hamed Mohammadi Elham Yaghubi Zahra Fakhri Hajar Tavakoli Ehsan Ghaedi Ali Keshavarz Mahnaz Zarei Mohammad Amin Shahrbaf Narges Ghandi Mina Darand Mohamad Hassan Javanbakht 《Phytotherapy research : PTR》2020,34(4):859-866
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