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In the human hypothalamus, arginine-vasopressin (AVP) is produced for a major part by the neurones of the supraoptic nucleus (SON). Since plasma AVP levels in men were reported to be higher than those of women and we did not find a sex difference in the neurone number, a higher vasopressinergic neurone activity was supposed to be present in the SON of men. Therefore we studied the size of the Golgi-apparatus (GA), which has been demonstrated previously to be a sensitive parameter for protein synthetic ability of neurones, in 15 men and 17 women ranging in age from 29 to 94 years. A polyclonal antibody against immunoaffinity purified MG-160, a sialoglycoprotein of the medial cisternae of the GA was applied on paraffin-embedded sections containing the dorsolateral SON (dl-SON) from which 90-95% of neurones are vasopressinergic. SON areas that contain oxytocin (OT) cells were excluded on the basis of adjacent sections stained with a monoclonal antibody against OT. By means of an image analysis system the size of the GA and the cellular profile area were determined in dl-SON neurones with a nucleolus. Our results showed indeed an age-dependent sex difference in the size of the GA that appeared to be twice as large in young men (< or = 50 years old) than in young women of the same age. The size of the GA increased with age in women but not in men. In addition, the mean cell profile area, another measure for neuronal activity, was significantly larger in young men than in young women and was in old women larger than in young women. In conclusion, these data show the presence of a sex-dependent age-difference in the activity of vasopressinergic neurones in dl-SON which may relate to differences in AVP and sex hormone levels and kidney AVP receptors.  相似文献   
5.
Graphene is fundamentally a two-dimensional material with extraordinary optical, thermal, mechanical, and electrical characteristics. It has a versatile surface chemistry and large surface area. It is a carbon nanomaterial, which comprises sp2 hybridized carbon atoms placed in a hexagonal lattice with one-atom thickness, giving it a two-dimensional structure. A large number of synthesis techniques including epitaxial growth, liquid phase exfoliation, electrochemical exfoliation, mechanical exfoliation, and chemical vapor deposition are used for the synthesis of graphene. Graphene prepared using different techniques can have a number of benefits and deficiencies depending on its application. This study provides a summary of graphene preparation techniques and critically assesses the use of graphene, its derivates, and composites in environmental applications. These applications include the use of graphene as membrane material for the detoxication and purification of water, active material for gas sensing, heavy metal ions detection, and CO2 conversion. Furthermore, a trend analysis of both synthesis techniques and environmental applications of graphene has been performed by extracting and analyzing Scopus data from the past ten years. Finally, conclusions and outlook are provided to address the residual challenges related to the synthesis of the material and its use for environmental applications.  相似文献   
6.
This study aimed to evaluate the physicochemical, structural, antioxidant and antibacterial properties of chitosan-coated (0.5 and 1% CH) nanoliposomes containing hydrolyzed protein of Spirulina platensis and its stability in simulated gastric and intestine fluids. The chitosan coating of nanoliposomes containing Spirulina platensis hydrolyzed proteins increased their size and zeta potential. The fourier transform infrared spectroscopy (FT-IR) test showed an effective interaction between the hydrolyzed protein, the nanoliposome, and the chitosan coating. Increasing the concentration of hydrolyzed protein and the percentage of chitosan coating neutralized the decreasing effect of microencapsulation on the antioxidant activity of peptides. Chitosan coating (1%) resulted in improved stability of size, zeta potential, and poly dispersity index (PDI) of nanoliposomes, and lowered the release of the hydrolyzed Spirulina platensis protein from nanoliposomes. Increasing the percentage of chitosan coating neutralized the decrease in antibacterial properties of nanoliposomes containing hydrolyzed proteins. This study showed that 1% chitosan-coated nanoliposomes can protect Spirulina platensis hydrolyzed proteins and maintain their antioxidant and antibacterial activities.  相似文献   
7.
A healthy society is the foundation of development in every country, and one way to achieve a healthy society is to promote healthy nutrition. An unbalanced diet is one of the leading causes of noncommunicable diseases globally. If food was correctly selected and correctly consumed, both the problems of overeating and lack of nutrition could be largely solved while also decreasing public health costs. Interventions such as presenting necessary information and warning labels would help consumers make better food choices. Hence, providing nutritional information to consumers becomes essential. The present study investigates the importance of nutrition information labels on consumers’ preferences by estimating their willingness to pay for features and information provided by a dietary software program (app). An application can easily display the information to the consumers and help them make informed food choices. A discrete choice experiment investigated consumers’ preferences and willingness to pay to receive nutritional information. Mixed multinomial logit and latent class analysis were applied. The results showed the existence of heterogeneity in consumer preferences for different nutritional information provided by the application. Consumers are willing to pay more for salt and fat alerts. The results of this study allow for the analysis of consumers’ interest in nutritional information. Such results are essential for the industry for future investments in similar applications that potentially could help consumers make better informed choices.  相似文献   
8.
Depression, a leading cause of disability worldwide, is also the most prevalent psychiatric problem among Parkinson disease patients. Both depression and Parkinson disease are associated with microstructural anomalies in the brain. Diffusion tensor imaging techniques have been developed to characterize the abnormalities in cerebral tissue. We included 11 studies investigating brain microstructural abnormalities in depressed Parkinson''s disease patients. The included studies found alterations to essential brain structural networks, including impaired network integrity for specific cortical regions, such as the temporal and frontal cortices. Additionally, findings indicate that microstructural changes in specific limbic structures, such as the prefronto‐temporal regions and connecting white matter pathways, are altered in depressed Parkinson''s disease compared to non‐depressed Parkinson''s disease and healthy controls. There remain inconsistencies between studies reporting DTI measures and depression severity in Parkinson disease participants. Additional research evaluating underlying neurobiological relationships between major depression, depressed Parkinson''s disease, and non‐depressed Parkinson''s disease is required to disentangle further mechanisms that underlie depression and related somatic symptoms, in Parkinson disease.  相似文献   
9.

Ethnopharmacological relevance

Fruits of Heracleum persicum (Apiaceae) are used as pain killer in Iranian folkloric medicine.

Aims of study

To evaluate the anti-inflammatory and analgesic effects of the hydroalcoholic extract and essential oil of the plant fruits and analyzing the essential oil.

Materials and methods

Essential oil and hydroalcoholic extracts of the fruits were prepared according to standard methods and the components of essential oil were identified using GC–MS method. The acetic acid-induced writhing response and formalin test were used in male mice to assess analgesic activity. For evaluation of anti-inflammatory effect, carrageenan-induced rat paw edema was used.

Results

Hexyl butyrate (56.5%), octyl acetate (16.5%), hexyl 2-methylbutanoate (5.2%) and hexyl isobutyrate (3.4%) were identified as the major constituents of the oil. Oral or intraperitoneal administration of Heracleum persicum essential oil (HPEO) at doses of 50–200 mg/kg and Heracleum persicum hydroalcoholic extract (HPHE) at doses of 250 and 500 mg/kg significantly reduced acetic acid-induced abdominal constrictions. HPEO and HPHE also significantly attenuated the pain response of the second phase of formalin test.In carrageenan test HPEO at doses of 100 and 200 mg/kg and HPHE at a dose of 400 mg/kg induced a significant reduction of paw edema.

Conclusions

These results clearly show the analgesic and anti-inflammatory effects of the plant essential oil and hydroalcoholic extract. Further studies are needed to clarify the mechanism of action and the components responsible for these pharmacological effects.  相似文献   
10.

Rational

A growing body of evidence illustrates that 5-HT3 receptor antagonist drugs may be of benefit in the treatment of negative symptoms in schizophrenia.

Objective

The objective of this study was to assess the efficacy and tolerability of tropisetron add-on to risperidone on negative symptoms in patients with chronic stable schizophrenia.

Methods

In a double-blind, placebo-controlled 8-week trial, 40 patients with chronic schizophrenia who were stabilized on risperidone were randomized into tropisetron or placebo add-on groups. Psychotic symptoms were measured using the Positive and Negative Syndrome Scale (PANSS) every 2 weeks. Furthermore, extrapyramidal and depressive symptoms as well as side effects were assessed. The primary outcome measure was the difference in change from baseline of negative subscale scores between the two groups at week 8.

Results

Tropisetron resulted in greater improvement of the total PANSS scores [F(1.860,70.699)?=?37.366, p?<?0.001] as well as negative scores [F(2.439,92.675)?=?16.623, p?<?0.001] and general psychopathology [F(1.767,67.158)?=?4.602, p?=?0.017], but not positive subscale scores [F(1.348, 51.218)?=?0.048, p?=?0.893] compared to placebo. In a multiple regression analysis controlling for positive, extrapyramidal, and depressive symptoms, treatment group (standardized β?=??0.640) significantly predicted changes in primary negative symptoms. The side effect profile did not differ significantly between the two groups.

Conclusion

Tropisetron add-on to risperidone improves the primary negative symptoms of patients with chronic stable schizophrenia.  相似文献   
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