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81.
Eva Nártová Jaroslav Kraus Emil Pavlík Petr Lukeš Rami Katra Jan Plzák Libuše Kolářová Ivan Šterzl Jan Betka Jaromír Astl 《European archives of oto-rhino-laryngology》2014,271(3):607-613
Helicobacter pylori, a well-known gastric pathogen, has been detected in the oral cavity and oropharynx in tonsillar tissue. In our study, the presence of H. pylori in the tonsillar tissue of patients with chronic tonsillitis and sleep apnoea syndrome (SAS) was investigated. The aim was to detect and genotype H. pylori for a collection of data supporting the possible role of H. pylori in the aetiology of chronic tonsillitis and SAS. Helicobacter pylori was detected by real-time polymerase chain reaction (rt-PCR). 89 patients, 60 with a diagnosis of chronic tonsillitis and 29 with SAS, were tested. In the chronic tonsillitis group, Helicobacter was detected in 48 (80 %) specimens, cagA gene was detected in 12 samples (25 %) and 12 samples were negative. In SAS group, Helicobacter was found in 24 samples (82.76 %), cagA gene was detected in 5 (20.83 %) and 5 samples (17.24 %) were negative. Helicobacter pylori-specific immunoglobulins were tested by ELISA in the serum of 57 patients only with 41 (71.93 %) showing positive. Our results on H. pylori DNA detection and H. pylori seropositivity show 26.32 % discrepancy, slightly in favour of rt-PCR (15.79 % compared to 10.53 %). The H. pylori presence in tonsillar tissue does not depend on the type of oropharyngeal disease (p = 0.756). This study shows that oropharynx constitutes an extragastric reservoir of H. pylori infection which could serve as an aetiopathogenetic factor for chronic tonsillitis and tonsillar hyperplasia by SAS. No conclusion has yet been drawn about the mechanism of the process. 相似文献
82.
Alexander N. Larcombe Melissa G. Papini Emily K. Chivers Luke J. Berry Robyn M. Lucas Caitlin S. Wyrwoll 《Environmental health perspectives》2021,129(1)
Background: Climate change models predict that atmospheric carbon dioxide [] levels will be between 700 and 900 ppm within the next 80 y. Despite this, the direct physiological effects of exposure to slightly elevated atmospheric (as compared with experienced today), especially when exposures extend from preconception to adulthood, have not been thoroughly studied.Objectives: In this study we aimed to assess the respiratory structure and function effects of long-term exposure to from preconception to adulthood using a mouse model.Methods: We exposed mice to () from prepregnancy, through the in utero and early life periods, until 3 months of age, at which point we assessed respiratory function using the forced oscillation technique, and lung structure.Results: exposure resulted in a range of respiratory impairments, particularly in female mice, including higher tissue elastance, longer chord length, and lower lung compliance. Importantly, we also assessed the lung function of the dams that gave birth to our experimental subjects. Even though these mice had been exposed to the same level of increased for a similar amount of time (), we measured no impairments in lung function. This suggests that the early life period, when lungs are undergoing rapid growth and development, is particularly sensitive to .Discussion: To the best of our knowledge, this study, for the first time, shows that long-term exposure to environmentally relevant levels of can impact respiratory function in the mouse. https://doi.org/10.1289/EHP7305 相似文献
83.
Luke A. Massey MRCP Caroline Micallef MD FRCR Dominic C. Paviour PhD Sean S. O'Sullivan PhD MRCPI Helen Ling BScMed BMBS MSc David R. Williams PhD Constantinos Kallis PhD Janice L. Holton PhD FRCPath Tamas Revesz MD FRCPath David J. Burn MD FRCP Tarek Yousry Dr med Habil FRCR Andrew J. Lees MD FRCP Nick C. Fox PhD FRCP Hans R. Jäger MD FRCR 《Movement disorders》2012,27(14):1754-1762
Conventional magnetic resonance imaging (cMRI) is often used to aid the diagnosis of progressive supranuclear palsy (PSP) and multiple system atrophy (MSA), but its ability to predict the histopathological diagnosis has not been systematically studied. cMRI from 48 neuropathologically confirmed cases, including PSP (n = 22), MSA (n = 13), Parkinson's disease (PD) (n = 7), and corticobasal degeneration (n = 6), and controls (n = 9) were assessed blinded to clinical details and systematically rated for reported abnormalities. Clinical diagnosis and macroscopic postmortem findings were retrospectively assessed. Radiological assessment of MRI was correct in 16 of 22 (72.7%) PSP cases and 10 of 13 (76.9%) MSA cases with substantial interrater agreement (Cohen's kappa 0.708; P < .001); no PSP case was misclassified as MSA or vice versa. MRI was less sensitive but more specific than clinical diagnosis in PSP and both more sensitive and specific than clinical diagnosis in MSA. The “hummingbird” and “morning glory” signs were highly specific for PSP, and “the middle cerebellar peduncle sign” and “hot cross bun” for MSA, but sensitivity was lower (up to 68.4%) and characteristic findings may not be present even at autopsy. cMRI, clinical diagnosis, and macroscopic examination at postmortem have similar sensitivity and specificity in predicting a neuropathological diagnosis. We have validated specific radiological signs in pathologically confirmed PSP and MSA. However, the low sensitivity of these and macroscopic findings at autopsy suggest a need for imaging techniques sensitive to microstructural abnormalities without regional atrophy. © 2012 Movement Disorder Society 相似文献
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Peter Luke BSc MSc Ewen Shepherd MBChB FRCP Tim Irvine MBChB FRCP Rae Duncan MBChB MSc MRCP 《Echocardiography (Mount Kisco, N.Y.)》2020,37(12):2163-2167
Inadvertent endocardial lead malposition is recognized as a rare incident which is usually underreported and if recognized during implantation can be easily corrected. This phenomenon is caused by the ventricular lead unintentionally crossing a pre-existing patent foremen ovale, septal defects (atrial or ventricular) or directly from the aorta via an accidental subclavian puncture resulting in the lead implanting into the left ventricle. While this is a rare occurrence we report, the incidental finding of pacemaker lead malposition during a routine follow-up transthoracic echocardiogram and the benefits of three-dimensional transesophageal echocardiography in this patient prior to lead extraction. 相似文献
89.
Luke M. Alvey James F. X. Jones Cathal Tobin‐O'Brien Mark Pickering 《Journal of anatomy》2019,234(2):165-178
The precise cause of the bands of Fontana, striations on peripheral nerves visible to the naked eye, has been the subject of debate for hundreds of years. Some researchers have described them as reflecting the sinuous course of nerve fibres passing through nerves, and others have proposed that endoneurial collagen and sheaths surrounding nerves play a role in their appearance. We hypothesised that the bands are caused exclusively by reflection of light from the surfaces of nerve fibres travelling in phase in sinusoidal waveforms through peripheral nerves. We aligned images of obliquely illuminated nerves with confocal images of axons in those nerves, and the numbers and positions of the bands precisely matched the axonal waves. We also developed three‐dimensional models of nerves with representations of the sinusoidal path of axons at their surface. We observed patterns resembling the bands of Fontana when these models were obliquely illuminated. This provides evidence that the bands of Fontana can be caused by light reflected sinusoidal path of axons alone. We subsequently describe a mechanism of band production based on our observations of both nerves and models. We report that smaller diameter nerves such as phrenic nerves and distal branches of sciatic nerves have shorter band intervals than larger nerves, such as proximal trunks of sciatic nerves, and that shorter band intervals correlate with longer axons per unit length of nerve, which suggests a greater tolerance to stretch. Inspection of banding patterns on peripheral nerves may permit prediction of axon length within nerves, and assist in the interpretation of nerve conduction data, especially in diseases where axon path has become altered. 相似文献
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