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The linkage between the macrolide efflux gene mef(I) and the chloramphenicol inactivation gene catQ was first described in Streptococcus pneumoniae (strain Spn529), where the two genes are located in a module designated IQ element. Subsequently, two different defective IQ elements were detected in Streptococcus pyogenes (strains Spy029 and Spy005). The genetic elements carrying the three IQ elements were characterized, and all were found to be Tn5253 family integrative and conjugative elements (ICEs). The ICE from S. pneumoniae (ICESpn529IQ) was sequenced, whereas the ICEs from S. pyogenes (ICESpy029IQ and ICESpy005IQ, the first Tn5253-like ICEs reported in this species) were characterized by PCR mapping, partial sequencing, and restriction analysis. ICESpn529IQ and ICESpy029IQ were found to share the intSp23FST81 integrase gene and an identical Tn916 fragment, whereas ICESpy005IQ has int5252 and lacks Tn916. All three ICEs were found to lack the linearized pC194 plasmid that is usually associated with Tn5253-like ICEs, and all displayed a single copy of a toxin-antitoxin operon that is typically contained in the direct repeats flanking the excisable pC194 region when this region is present. Two different insertion sites of the IQ elements were detected, one in ICESpn529IQ and ICESpy029IQ, and another in ICESpy005IQ. The chromosomal integration of the three ICEs was site specific, depending on the integrase (intSp23FST81 or int5252). Only ICESpy005IQ was excised in circular form and transferred by conjugation. By transformation, mef(I) and catQ were cotransferred at a high frequency from S. pyogenes Spy005 and at very low frequencies from S. pneumoniae Spn529 and S. pyogenes Spy029.  相似文献   
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Little is known about the development of psychosis during hydroxychloroquine (HCQ) treatment, especially in elderly patients affected by rheumatic diseases, with multiple comorbidities and treatments. To summarize the available evidence on HCQ-induced psychosis in elders, we performed a literature review. Additionally, individual case safety reports sent to the European Pharmacovigilance database (EudraVigilance) with HCQ as suspected drug and related to adverse events belonging to the System Organ Class ‘Psychiatric disorders’ were shown. Over the years, evidence was published about the risk of neuropsychiatric clinical manifestations during HCQ treatment for rheumatic diseases, but few of them were related to elderly patients. These adverse events can include less severe clinical manifestations such as affect lability and nervousness or more severe conditions such as actual psychosis and suicidal tendencies, which frequency are actually unknown. The presence of risk factors in these patients may precipitate HCQ-induced psychosis and their precocious detection could be associated with a risk minimization. Among predisposing risk factors, there are the co-exposure to interacting drugs, alcohol intake, familial history of psychiatric diseases, female gender, and the concomitant use of low-dose glucocorticoids. In some cases it was possible to reverse psychotic behaviour with the antipsychotic treatment or with HCQ suspension.  相似文献   
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Chronic autoimmune atrophic gastritis (CAAG) is an organ-specific autoimmune disease, which affects the corpus–fundus gastric mucosa. Although it has been described for several years, the real pathophysiological mechanisms, the natural history and the possible neoplastic complications are not completely known. Atrophy of the gastric mucosa is the endpoint of the chronic processes, with the loss of glandular cells and their replacement by intestinal-type epithelium, pyloric-type glands, and fibrous tissue. As a consequence, hydrochloric acid, pepsin and intrinsic-factor is impaired resulting in pernicious anemia. The exact causal agent is not yet known, but both genetic and environmental factors seem to play a decisive role.Moreover, the clinical onset may assume different characteristics; differently from what previously observed, recent evidence has reported the onset of CAAG at a younger age, frequently with iron deficiency anemia or upper gastro-intestinal symptoms.The diagnosis of CAAG might be challenging and usually requires the combination of clinical, serological and histopathologic data; moreover, CAAG patients are often misdiagnosed as refractory to HP eradication therapy, probably because achlorhydria might allow urease-positive bacteria other than H pylori to colonize the stomach, causing positive 13C-urea breath test results.However, biopsy is the most reliable method to evaluate the presence of metaplastic atrophic gastritis. In order to assess the severity of gastric atrophy and intestinal metaplasia, OLGA and OLGIM staging systems have been proposed and seem to correlate with the risk of developing gastric adenocarcinoma. Indeed, CAAG represents a pre-neoplastic condition, as patients with CAAG are very likely to develop either type-1 gastric neuroendocrine tumors and gastric adenocarcinomas, as well as several other neoplastic diseases. To date, the need, the intervals and cost-effectiveness of endoscopic/histological surveillance for patients with CAAG/pernicious anemia are yet to be established.  相似文献   
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Nerve growth factor (NGF), a member of the neurotrophin family, was initially described as neuronal survival and growth factor, but successively has emerged as an active mediator in many essential functions in the central nervous system of mammals. NGF is synthesized as a precursor pro‐NGF and is cleaved intracellularly into mature NGF. However, recent evidence demonstrates that pro‐NGF is not a simple inactive precursor, but is also secreted outside the cells and can exert multiple roles. Despite the vast literature present in mammals, studies devoted to NGF in the brain of other vertebrate models are scarce. Zebrafish is a teleost fish widely known for developmental genetic studies and is well established as model for translational neuroscience research. Genomic organization of zebrafish and mouse NGF is highly similar, and zebrafish NGF protein has been reported in mature and two‐precursors forms. To add further knowledge on neurotrophic factors in vertebrate brain models, we decided to determine the NGF mRNA and protein distribution in the adult zebrafish brain and to characterize the phenotype of NGF‐positive cells. NGF mRNA was visualized by in situ hybridization on whole‐mount brains. NGF protein distribution was assessed on microtomic sections by using an antiserum against NGF, able to recognize pro‐NGF in adult zebrafish brain as demonstrated also in previous studies. To characterize NGF‐positive cells, anti‐NGF was employed on microtomic slides of aromatase B transgenic zebrafish (where radial glial cells appeared fluorescent) and by means of double‐immunolabeling against NGF/proliferative cell nuclear antigen (PCNA; proliferation marker) and NGF/microtube‐associated protein2 (MAP2; neuronal marker). NGF mRNA and protein were widely distributed in the brain of adult zebrafish, and their pattern of distribution of positive perikaryal was overlapping, both in males and females, with few slight differences. Specifically, the immunoreactivity to the protein was observed in fibers over the entire encephalon. MAP2 immunoreactivity was present in the majority of NGF‐positive cells, throughout the zebrafish brain. PCNA and aromatase B cells were not positive to NGF, but they were closely intermingled with NGF cells. In conclusion, our study demonstrated that mature neurons in the zebrafish brain express NGF mRNA and store pro‐NGF.  相似文献   
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We report 50 patients who had sinus lift operations between 1995 and 1999 using different grafting materials [autologous bone, heterologous bone, and hydroxyapatite]. The casenote were analysed clinically (intraoperative and postoperative results and complications), radiographically (amount of augmented bone 6 months postoperatively), and histologically (quality of the new bone 12 months postoperatively). Our aim was to find out if the various bone grafting materials used resulted in different outcomes after adjustment for significant predictors. We found that hydroxyapatite was associated with the lowest rate of loss of grafted material (median, 2.4 mm) followed by the autologous bone from iliac crest (2.8 mm). Bovine bone shown the highest loss (3.3 mm).  相似文献   
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The sample of patients analyzed has been selected from 66 cases treated for extraoral bone-anchored implantology at the Plastic and Reconstructive Surgery Department of the "Tor Vergata" University of Rome. Optimal results can be obtained in the ear district because of the low surgical risks and few postsurgical complications. Advantages offered by extraoral bone integrated implants are obvious when compared with more traditional techniques: it is possible to obtain a better cosmetic result only from 2 surgical sessions; and adhesive prosthesis may be better placed without the usual local irritation, achieving a correct positioning. The authors present their experiences in using extraoral implants for the reconstruction of the ear area malformation.  相似文献   
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