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1.
Paraquat (1,1'-dimethyl-4,4'-bipyridinium), a widely used non-selective herbicide, is a redox cycling agent with adverse effects on dopamine systems. Epidemiological data have shown that exposure to paraquat is one of the several risk factors for Parkinson's disease. We have already shown that cyclo(His-Pro), an endogenous cyclic dipeptide produced by the cleavage of the thyrotropin releasing hormone, has a cytoprotective effect through a mechanism involving Nrf2 activation that decreases production of reactive oxygen species and increases glutathione synthesis. Using primary neuronal cultures and PC12 cells as targets of paraquat neurotoxicity, we addressed whether and how cyclo(His-Pro) causes cellular protective response against paraquat-mediated cell death. We found that cyclo(His-Pro) attenuated reactive oxygen species production, and prevented glutathione depletion by up-regulating Nrf2 gene expression, triggering its nuclear accumulation and activating the expression of heme oxygenase1. These protective effects were abolished by RNA interference-mediated Nrf2 knock down whereas were unaffected by RNA interference-mediated Keap1 knock down. Inhibition of heme oxygenase activity decreased cyclo(His-Pro)-induced neuroprotection. These results suggest that cyclo(His-Pro), acting as a selective activator of the brain modulable Nrf2 pathway, may be a promising candidate as neuroprotective agent that act through induction of phase II genes.  相似文献   
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Abstract The expression of nitrite reductase has been tested in a wild-type strain of Pseudomonas aeruginosa (Pao1) as a function of nitrate concentration under anaerobic and aerobic conditions. Very low levels of basal expression are shown under non-denitrifying conditions (i.e. absence of nitrate, in both aerobic and anaerobic conditions); anaerobiosis is not required for high levels of enzyme production in the presence of nitrate. A Pseudomonas aeruginosa strain, mutated in the nitrite reductase gene, has been obtained by gene replacement. This mutant, the first of this species described up to now, is unable to grow under anaerobic conditions in the presence of nitrate. The anaerobic growth can be restored by complementation with the wild-type gene.  相似文献   
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XANES study of iron displacement in the haem of myoglobin   总被引:1,自引:0,他引:1  
The XANES (X-ray absorption near edge structure) spectra of deoxy human adult haemoglobin (HbA) and myoglobin (Mb) have been measured at the wiggler beam line of the Frascati synchrotron radiation facility. The XANES are interpreted by the multiple scattering cluster theory. The variations in the XANES between HbA and Mb are assigned to changes in the Fe-porphyrin geometry.  相似文献   
4.
Summary HLA genotype and HLA-linked marker data for 40 unrelated patients from central Italy and 2 unrelated patients from Sardinia with congenital adrenal hyperplasia due to 21-hydroxylase deficiency (21-OH-def) were analyzed. The results confirm that the HLA-linked 21-OH-def gene is associated with several different HLA determinants and complete HLA haplotypes, although the only determinant with significantly increased frequency was the complement C2 allele C2B. The HLA antigens B8 and DR3 were found in significantly decreased frequencies. The haplotype A3, Cw6, Bw47, BfF, DR7, which is exceptionally rare in the general population but which has been found in many other 21-OH-def patients from diverse geographical origins, was also found in one of the Italian patients. This and other HLA haplotype associations found among the Italian patients may represent mutations that have occurred on HLA haplotypes with genetic linkage disequilibrium or, alternatively, may represent mutations that have not yet had time to become randomly associated with different HLA complex determinants. The marked negative associations with B8 and DR3 could, however, result from an interaction between the gene products of the HLA complex and the 21-OH-def phenotype.  相似文献   
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Mutations in nuclear-encoded protein subunits of the mitochondrial ribosome are an increasingly recognised cause of oxidative phosphorylation system (OXPHOS) disorders. Among them, mutations in the MRPL44 gene, encoding a structural protein of the large subunit of the mitochondrial ribosome, have been identified in four patients with OXPHOS defects and early-onset hypertrophic cardiomyopathy with or without additional clinical features. A 23-year-old individual with cardiac and skeletal myopathy, neurological involvement, and combined deficiency of OXPHOS complexes in skeletal muscle was clinically and genetically investigated. Analysis of whole-exome sequencing data revealed a homozygous mutation in MRPL44 (c.467 T?>?G), which was not present in the biological father, and a region of homozygosity involving most of chromosome 2, raising the possibility of uniparental disomy. Short-tandem repeat and genome-wide SNP microarray analyses of the family trio confirmed complete maternal uniparental isodisomy of chromosome 2. Mitochondrial ribosome assembly and mitochondrial translation were assessed in patient derived-fibroblasts. These studies confirmed that c.467 T?>?G affects the stability or assembly of the large subunit of the mitochondrial ribosome, leading to impaired mitochondrial protein synthesis and decreased levels of multiple OXPHOS components. This study provides evidence of complete maternal uniparental isodisomy of chromosome 2 in a patient with MRPL44-related disease, and confirms that MRLP44 mutations cause a mitochondrial translation defect that may present as a multisystem disorder with neurological involvement.

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7.
Abstract

Benthic marine flora of Tuscan Archipelago has been studied. Several samples were collected along five islands and some rocks. This paper is a compendium of new and already published data, in which 267 species, varieties, forms and stadia of algae and seagrasses are listed: 5 Bangiophyceae, 182 Florideophyceae, 45 Phaeophyceae, 6 Chlorophyceae, 28 Bryopsidophyceae, 1 Angiospermae.  相似文献   
8.

Background

The opinions held by the general population on obstructive lung disease and inhaler devices could influence asthma and chronic obstructive pulmonary disorder (COPD) management and treatment adherence.The aim of the present public pragmatic survey was to evaluate the opinions, beliefs and perceptions of Italian people with respect to respiratory diseases as well as their perspectives on the use of inhaler devices.

Methods

This survey was conducted on a group of 2,008 individuals forming a representative sample of the Italian population aged 15 years and over. It was based on personal interviews that were administered in the homes of the respondents using a structured questionnaire that took approximately 30 minutes.

Results

Awareness of obstructive lung diseases is poor. Asthma, but not COPD, was perceived as a common and increasingly prevalent disease by the majority of the interviewees. Allergy, pollution and smoking were considered to be responsible for both of these diseases. The rates at which the respondents claimed to be suffering from asthma and COPD were lower than expected (4% and 2%, respectively). Inhaled drugs were recognised as the main treatment by 65% of the respondents. The great majority of respondents attributed positive characteristics to the inhaler device (e.g., safety, reliability, effectiveness, ease of use and practicality). Compared to people who have never used inhaler devices, individuals who suffer from asthma or COPD were more confident in their use and showed a greater belief in their safety, reliability and trustworthiness. People older than 64 years showed less attention to the properties of these devices.

Conclusions

The present results highlight the need for public interventions aimed at improving awareness of obstructive lung disease and reveal various potentialities and critical issues for inhaler device usage. Switching of devices was considered feasible by most of the interviewees, as long as the choice is carefully explained by their physician.  相似文献   
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