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Impaired olfaction is an early symptom of Parkinson's disease. The underlying neuropathology likely includes α‐synucleinopathy in the olfactory bulb at an earlier stage (Braak's stage1) than pathology in the substantia nigra, which is not observed until stage 3. In this report, we investigated the distribution and cell types affected by α‐synuclein in the olfactory bulb of transgenic mice (2–8 months of age) expressing the human A53T variant of α‐synuclein. α‐Synuclein immunostaining progressively affects interneurons and mitral cells. Double labeling studies demonstrate that dopaminergic cells are hardly involved, whereas glutamatergic‐ and calcium binding protein‐positive cells are severely affected. This temporal evolution and the cell types expressing α‐synuclein are reminiscent of idiopathic Parkinson's disease and support the usefulness of this model to address specific topics in the premotor phase of the disease. © 2010 Movement Disorder Society  相似文献   
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Sjögren's Syndrome (SS) is a chronic autoimmune disorder of the exbaocrine glands with associated lymphocytic infiltrates of the affected glands. SS occurs in a primary form not associated with other diseases and in a secondary form that complicates other rheumatic conditions. In both primary and secondary SS, decreased exocrine gland function leads to the “sicca complex”, a combination of dry eyes (xerophthalmia) and dry mouth (xerostomia). The clinical manifestations also include extraglandular disease features (skin, joints and muscles, lungs, kidneys, gastrointestinal tract). A variety of classification schemes have been proposed and discussed in the literature since the 1980s. The latest criteria, known as the American-European classification criteria for SS, were proposed in 2002. These criteria suggest that diagnosis of primary SS requires 4 of 6 criteria, including a positive minor-salivary biopsy sample and/or SS-A/SS-B antibodies. Therapy can be grouped into two separate aspects: treatment of dry eyes and dry mouth (replacement tears, muscarinic agonist agents…) and treatment of extraglandular manifestations (steroidal and non-steroidal anti-inflammatory agents, disease modifying agents, cytotoxic agents and biological therapies).  相似文献   
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The in vitro effects of flurochloridone (FLC) and its formulations Twin Gold Pack® (25% a.i.) and Rainbow® (25% a.i.) were evaluated on Chinese hamster ovary (CHO-K1) cells by genotoxicity [sister chromatid exchange (SCE)] and cytotoxicity [cell-cycle progression, proliferative rate index (PRI), mitotic index (MI), MTT, and neutral red] end points. Cells were treated for 24 h within the 0.25–15 μg/ml concentration range. FLC and Twin Pack Gold® induced a significant and equivalent increase in SCEs regardless of the concentration. Rainbow®-induced SCEs at concentrations higher than 2.5 μg/ml; however, the increases were always lower than those induced by FLC and Twin Pack Gold®. For all compounds, the PRI decreased as a function of the concentration titrated into cultures. Whereas only the highest FLC and Twin Pack Gold® concentrations induced a significant reduction of the MI, all tested Rainbow® concentrations induced MI inhibition. Overall, the results demonstrated that although all compounds were not able to reduce the lysosomal activity, the mitochondrial activity was diminished when the highest concentrations were employed. These observations represent the first study analyzing the genotoxic and cytotoxic effects exerted by FLC and two formulated products on mammalian cells in vitro, at least on CHO-K1 cells.  相似文献   
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Minthostachys verticillata (peperina) is an aromatic and medicinal plant with several uses and ethnobotanical properties. Numerous studies have demonstrated that its essential oil (Mv-EO) presents antimicrobial capacity and shows immunomodulating and anti-allergic properties in human cell lines. Thus, the goal of this study was to investigate the main chemical composition, analyzed by GC–FID, and the cyto-genotoxic effects of Mv-EO, using Vero cells, human PBMCs and mice bone marrow cells. The Mv-EO was rich in pulegone 60.5% and menthone 18.2%. Our results clearly show that Mv-EO is not cyto-genotoxic in vitro nor in vivo. It not induced cytotoxic effects, as indicated by trypan blue dye exclusion and NRU assays both in Vero cells and human PBMCs. In addition, Mv-EO (100–1000 μg/mL) not induced apoptotic effects on human PBMCs, as indicated by Hoechst staining and DNA fragmentation analysis by agarose gel electrophoresis. The in vivo assay showed that Mv-EO (25–500 mg/kg) not increased the frequency of micronucleus in bone marrow cells of mice. Further, the ratio of polychromatic/normochromatic erythrocytes was not modified. These findings suggest that Mv-EO appears to be safe as a therapeutic agent.  相似文献   
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Nitric oxide (NO) produced by inducible nitric oxide synthase (iNOS) is a radical effector molecule of the innate immune system that can directly inhibit pathogen replication. In order to study subsequent iNOS kidney expression in experimental leptospirosis, Golden Syrian hamsters and C3H/HeJ mice were infected intraperitoneally with 102 or 107 virulent Leptospira interrogans serovar Copenhageni (LIC) strain Fiocruz L1-130. Results showed increased levels of iNOS mRNA and protein in kidneys of infected animals when compared to that in mock-infected animals. To get a deeper insight into the role of iNOS in experimental leptospirosis, both subject species were treated or not treated with 4-aminopyridine (4-AP, 0.3 mg/kg), an iNOS inhibitor. Treatment of infected hamsters with 4-AP accelerated the mortality rate to 100% by one day and increased the mortality rate from 20 to 60% in mice at 14 days post-infection. In kidney tissues, 4-AP treatment increased the bacterial burden, as demonstrated through leptospiral DNA quantification by real-time PCR, and aggravated tubulointerstitial nephritis. In addition, iNOS inhibition reduced the specific humoral response against LIC when compared to that in untreated infected animals. According to these results, iNOS expression and the resulting NO have an important role in leptospirosis.  相似文献   
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The COVID-19 pandemic and the implemented control measures have impacted the circulation of respiratory-transmitted pathogens. In this report, we present data from a retrospective study that included 17,883 specimens conducted between 2018 and 2022 in our facility, describing the dynamics of circulation of the main respiratory viruses. We observed a significant decrease in all viral detections (other than SARS-CoV-2) starting from March 2020. However, rhinovirus maintained comparable levels to the pre-pandemic period. Additionally, influenza viruses were not detected during the 2020–2021 season, and respiratory syncytial virus (RSV) exhibited a shift in its seasonality, with an epidemic peak occurring in the summer of 2021.  相似文献   
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Second branchial cleft anomalies are the most common of this type of neck masses. They can be classified in four types (Bailey/Proctor classification) according to their location. Type II is the most common, and related to vital neck structures such as the carotid artery and jugular vein. Cysts are the most frequent among them. Management consists of surgical excision of the cyst and tract by cervicotomy to avoid recurrence. We present an extremely rare case of a 32-year-old male who presented a sudden appearance of a right lateral neck mass that was identified by an image study as a double branchial cleft cyst. A review of simultaneous branchial cleft cyst in the literature is also made.  相似文献   
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