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991.
Christine M. Dejea Elizabeth C. Wick Elizabeth M. Hechenbleikner James R. White Jessica L. Mark Welch Blair J. Rossetti Scott N. Peterson Erik C. Snesrud Gary G. Borisy Mark Lazarev Ellen Stein Jamuna Vadivelu April C. Roslani Ausuma A. Malik Jane W. Wanyiri Khean L. Goh Iyadorai Thevambiga Kai Fu Fengyi Wan Nicolas Llosa Franck Housseau Katharine Romans XinQun Wu Florencia M. McAllister Shaoguang Wu Bert Vogelstein Kenneth W. Kinzler Drew M. Pardoll Cynthia L. Sears 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(51):18321-18326
Environmental factors clearly affect colorectal cancer (CRC) incidence, but the mechanisms through which these factors function are unknown. One prime candidate is an altered colonic microbiota. Here we show that the mucosal microbiota organization is a critical factor associated with a subset of CRC. We identified invasive polymicrobial bacterial biofilms (bacterial aggregates), structures previously associated with nonmalignant intestinal pathology, nearly universally (89%) on right-sided tumors (13 of 15 CRCs, 4 of 4 adenomas) but on only 12% of left-sided tumors (2 of 15 CRCs, 0 of 2 adenomas). Surprisingly, patients with biofilm-positive tumors, whether cancers or adenomas, all had biofilms on their tumor-free mucosa far distant from their tumors. Bacterial biofilms were associated with diminished colonic epithelial cell E-cadherin and enhanced epithelial cell IL-6 and Stat3 activation, as well as increased crypt epithelial cell proliferation in normal colon mucosa. High-throughput sequencing revealed no consistent bacterial genus associated with tumors, regardless of biofilm status. However, principal coordinates analysis revealed that biofilm communities on paired normal mucosa, distant from the tumor itself, cluster with tumor microbiomes as opposed to biofilm-negative normal mucosa bacterial communities also from the tumor host. Colon mucosal biofilm detection may predict increased risk for development of sporadic CRC.When healthy, the colon is covered by a mucus layer that segregates the microbiota from direct contact with the host colonic epithelium (1). Breaches of this protective mucus layer with resulting increased contact between mucosal microbiota and the colonic epithelial cells have been proposed as a critical first step in inciting changes in tissue biology and/or inflammation that yield inflammatory bowel disease (2–4). Concomitant with increased access to the mucosal epithelium, microbial community communication (such as quorum sensing) is predicted to change, thereby modifying microbial structure and function and often resulting in biofilm formation (5). Biofilms are defined as aggregations of microbial communities encased in a polymeric matrix that adhere to either biological or nonbiological surfaces. Biofilms that invade the colonic mucus layer and come into direct contact with mucosal epithelial cells indicate a pathologic state (6, 7). Biofilms characterize numerous chronic mucosal disease states in and outside of the colon (including inflammatory bowel diseases, pharyngo-tonsillitis, otitis media, rhinosinusitis, urethritis, and vaginitis), where direct bacterial contact with epithelial cells results in perturbed epithelial function and chronic inflammation (8). However, no association of biofilms with colorectal cancer (CRC) pathologic states has been reported. 相似文献
992.
ABSTRACTDeep brain stimulation (DBS) of the subthalamic nucleus (STN) improves the motor symptoms of Parkinson’s disease (PD). The STN may represent an important relay station not only in the motor but also the associative cortico-striato-thalamocortical pathway. Therefore, STN stimulation may alter cognitive functions, such as working memory (WM). We examined cortical effects of STN-DBS on WM in early PD patients using functional near-infrared spectroscopy. The effects of dopaminergic medication on WM were also examined. Lateral frontal activity during WM maintenance was greater when patients were taking dopaminergic medication. STN-DBS led to a trend-level worsening of WM performance, accompanied by increased lateral frontal activity during WM maintenance. These findings suggest that STN-DBS in PD might lead to functional modifications of the basal ganglia-thalamocortical pathway during WM maintenance. 相似文献
993.
Vincent Alvarez Andrea O. Rossetti Vasileios Papavasileiou Patrik Michel 《Journal of neurology》2013,260(1):55-61
Seizures appear at stroke presentation, during the acute phase or as a late complication of stroke. Thrombolysis has not been investigated as a risk factor despite its potential neurotoxic effect. We try to identify risk factors for seizures during the acute phase of ischemic stroke in a cohort including thrombolysed patients. We undertook a case–control study at a single stroke center using data from Acute Stroke Registry and Analyse of Lausanne (ASTRAL). Patients with seizure occurring during the first 7 days following stroke were retrospectively identified. Bi-variable and multivariable statistical analyses were applied to compare cases and randomly selected controls. We identified 28 patients experiencing from seizures in 2,327 acute ischemic strokes (1.2 %). All seizures occurred during the first 72 h. Cortical involvement, thrombolysis with rt-PA, arterial recanalization, and higher initial NIHSS were statistically associated with seizures in univariated analysis. Backward linear regression identified cortical involvement (OR 7.53, 95 % CI 1.6–35.2, p < 0.01) and thrombolysis (OR 4.6, 95 % CI 1.6–13.4, p = 0.01) as being independently associated with seizure occurrence. Overall, 3-month outcome measured by the modified Rankin scale (mRS) was comparable in both groups. In the subgroup of thrombolysed patients, outcome was significantly worse at 3 months in the seizure group with 9/12 (75 %) patients with mRS ≥3, compared to 6/18 (33.3 %) in the seizure-free group (p = 0.03). Acute seizures in acute ischemic stroke were relatively infrequent. Cortical involvement and thrombolysis with rt-PA are the principal risk factors. Seizures have a potential negative influence on clinical outcome in thrombolysed patients. 相似文献
994.
Benzodiazepine (BDZ), a widely recognized first‐line status epilepticus (SE) treatment, may lead to respiratory depression. This cohort study investigates the effect of BDZ doses in SE patients in terms of morbidity and mortality. It considers incident SE episodes from a prospective registry (2009–2012), comparing patients receiving standard BDZ dose to those receiving exceeding doses (>30% above recommended dose), in terms of likelihood to receive intubation, morbidity, and mortality. Duration of hospitalization was assessed for subjects needing intubation for airways protection (not for refractory SE treatment) versus matched subjects not admitted to the intensive care unit (ICU). We identified 29 subjects receiving “excessive” and 173 “standard” BDZ dose; 45% of the overtreated patients were intubated for airways protection, but only 8% in the standard‐dose group (p < 0.001). However, both groups presented similar clinical outcomes: 50% returned to baseline, 40% acquired a new handicap, and 10% died. Orotracheal intubation due to airways protection was associated with significantly longer hospitalization (mean 2 weeks vs. 1 week, p = 0.008). In conclusion, although administration of excessive BDZ doses in SE treatment does not seem to influence outcome, it is related to higher respiratory depression risk and longer hospitalization, potentially exposing patients to additional complications and costs. 相似文献
995.
Percy Bondallaz Colette Boëx Andrea O. Rossetti Giovanni Foletti Laurent Spinelli Serge Vulliemoz Margitta Seeck Claudio Pollo 《Seizure》2013,22(5):390-395
PurposeTo study the clinical outcome in hippocampal deep brain stimulation (DBS) for the treatment of patients with refractory mesial temporal lobe epilepsy (MTLE) according to the electrode location.MethodsEight MTLE patients implanted in the hippocampus and stimulated with high-frequency DBS were included in this study. Five underwent invasive recordings with depth electrodes to localize ictal onset zone prior to chronic DBS. Position of the active contacts of the electrode was calculated on postoperative imaging. The distances to the ictal onset zone were measured as well as atlas-based hippocampus structures impacted by stimulation were identified. Both were correlated with seizure frequency reduction.ResultsThe distances between active electrode location and estimated ictal onset zone were 11 ± 4.3 or 9.1 ± 2.3 mm for patients with a >50% or <50% reduction in seizure frequency. In patients (N = 6) showing a >50% seizure frequency reduction, 100% had the active contacts located <3 mm from the subiculum (p < 0.05). The 2 non-responders patients were stimulated on contacts located >3 mm to the subiculum.ConclusionDecrease of epileptogenic activity induced by hippocampal DBS in refractory MTLE: (1) seems not directly associated with the vicinity of active electrode to the ictal focus determined by invasive recordings; (2) might be obtained through the neuromodulation of the subiculum. 相似文献
996.
997.
Salvatore Tolone Ruggiero Roberto Gianmattia del Genio Luigi Brusciano Domenico Parmeggiani Vincenzo Amoroso Giuseppina Casalino Ignazio Verde Alfonso Bosco Antonio D'Alessandro Raffaele Pirozzi Gianluca Rossetti Paolo Limongelli Ludovico Docimo 《BMC surgery》2013,13(Z2):S11
Background
Hypocalcemia caused by transient or definitive hypoparathyroidism is the most frequent complication after total thyroidectomy (TT). We aimed to compare the impact of age and the clinical usefulness of oral calcium and vitamin D supplements on postoperative hypocalcemia after TT, and to determine which risk factors are important for hypocalcemia incidence.Methods
Two hundred consecutive patients treated by TT were included prospectively in the present study. All patients supplemented oral calcium and vitamin D in the post-operative time. The data concerning symptomatic and laboratoristichypocalcemia were collected.Patients were evaluated according to age, sex, postoperative serum calcium levels, and preoperative serum alkaline phosphatasis levels.Results
Symptomatic hypocalcemia developed only in 19 patients (9.5%), whereas laboratory hypocalcemia developed in 36 patients (18%). The risk for postoperative hypocalcemia was increate 20-fold for patients older than 50 years.Conclusions
Age is significantly associated with postoperative hypocalcemia. Implementing oral calcium and vitamin D after total thyroidectomy can reduce the incidence of hypocalcemia related to surgery.998.
Marco De Simone Michele Chirichella Stefan Emming Saveria Mazzara Valeria Ranzani Paola Gruarin Giorgia Moschetti Nadia Pulvirenti Stefano Maglie Chiara Vasco Maria Cristina Crosti Grazisa Rossetti Massimiliano Pagani Sergio Abrignani Silvia Monticelli Jens Geginat 《European journal of immunology》2021,51(12):3243-3246
999.
1000.