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101.
102.
Gleicy K. Barcelos Yannick Tholance Sebastien Grousson Bernard Renaud Armand Perret-Liaudet Frederic Dailler Luc Zimmer 《Neurocritical care》2013,18(2):234-244
Purpose
The aim of this study was to determine if the measurement of blood biomarkers of glucose cerebral metabolism, performed with retrograde jugular catheter, could predict the outcome of poor-grade aneurysmal subarachnoid hemorrhage (aSAH) patients.Methods
This study was conducted in 68 poor-grade aSAH patients. A total of 4,024 blood samples obtained from jugular and radial catheters were analyzed for glucose, lactate, and oxygen content every 8 h for 10 ± 0.5 days. Metabolic ratio (MR) and lactate–oxygen index (LOI) were obtained by ratios using arterio-jugular differences. Functional outcome was evaluated at 12 months with the Glasgow Outcome Scale.Results
Outcome was unfavorable in 40 patients. In this group of patients, the MR was significantly lower (p < 0.0001) and the LOI was significantly higher (p = 0.0001) than in the group with favorable outcome. The MR cutoff value, below which the patients are likely to have an unfavorable outcome, was determined to be 3.35. More interestingly, the data obtained in this study demonstrated that the patients achieving an unfavorable outcome were distinguished from those with a favorable outcome by having at least three events of MR inferior to 3.35 (sensitivity = 90 %, specificity = 82.1 %). Moreover, in patients who developed cerebral vasospasm, we observed a significant decrease in the MR.Conclusion
Our data provide additional support to the view that the MR is a reliable marker for predicting the outcome of poor-grade aSAH patients. Prospective studies are needed to confirm its value in multimodal monitoring. 相似文献103.
104.
Makaryan V Kulik W Vaz FM Allen C Dror Y Dale DC Aprikyan AA 《European journal of haematology》2012,88(3):195-209
Barth syndrome (BTHS), a rare, X-linked, recessive disease, is characterized by neutropenia and cardiomyopathy. BTHS is caused by loss-of-function mutations of the tafazzin (TAZ) gene. We developed a model of BTHS by transfecting human HL60 myeloid progenitor cells with TAZ-specific shRNAs. Results demonstrate a significant downregulation in TAZ expression, mimicking the effects of naturally occurring truncation mutations in TAZ. Flow cytometry analyses of cells with TAZ-specific, but not scrambled, shRNAs demonstrate nearly twofold increase in the proportion of annexin V-positive cells and significantly increased dissipation of mitochondrial membrane potential as determined by DIOC6 staining. Transfection of TAZ-specific shRNA had similar effects in U937 myeloid cells but not in lymphoid cell lines. Further studies in HL60 myeloid progenitor cells revealed aberrant release of cytochrome c from mitochondria and significantly elevated levels of activated caspase-3 in response to TAZ knockdown. Treatment with caspase-specific inhibitor zVAD-fmk resulted in substantially reduced apoptosis to near-normal levels. These data suggest that neutropenia in BTHS is attributable to increased dissipation of mitochondrial membrane potential, aberrant release of cytochrome c, activation of caspase-3, and accelerated apoptosis of myeloid progenitor cells, and that this defect can be partially restored in vitro by treatment with caspase-specific inhibitors. 相似文献
105.
Mabo P Defaye P Mouton E Cebron JP Davy JM Tassin A Babuty D Mondoly P Paziaud O Anselme F Daubert JC 《Journal of cardiovascular electrophysiology》2012,23(8):853-860
Impact of Recalls on ICD Utilization . Introduction: The study was designed to evaluate the feasibility and performance of right ventricular (RV) mid‐septal versus apical implantable defibrillator (ICD) lead placement. Methods and Results: SEPTAL is a randomized, noninferiority trial, which randomly assigned patients to implantation of ICD leads in the RV mid‐septum versus apex, with a primary objective of comparing the implant success rate of implant at each site, based on strict electrical predefined criteria. We also compared the (1) pacing lead characteristics, (2) rates of appropriate and inappropriate ICD therapies, and (3) all‐cause mortality between the 2 sites at 1 year. The trial enrolled 215 patients (mean age = 59.7 ± 12.4 years, mean LVEF = 34.0 ± 14.2%, 84.2% men), of whom 148 (68.8%) presented with ischemic heart disease. The ICD indication was primary prevention in 117 patients (54.4%). The lead was successfully implanted in 96/107 patients (89.7%) assigned to the RV mid‐septum, and in 99/108 (91.7%) assigned to the apex (ns). The 1‐year rate of lead‐related adverse events was similar in both groups. A total of 8 first inappropriate ICD therapies (7.9%) were delivered in the RV mid‐septal group, versus 8 (7.8%) in the apical group (ns), while first appropriate therapies were delivered to 22 (21.4%) and 24 patients (23.8%), respectively (ns). All‐cause mortality was 7.9% in the RV mid‐septal versus 2.9% in the RV apical group (ns). Conclusion: This study confirmed the technical feasibility and noninferior performance of ICD leads implanted in the RV mid‐septum versus the apex. (J Cardiovasc Electrophysiol, Vol. 23, pp. 853‐860, August 2012) 相似文献
106.
ES Charlson JM Diamond K Bittinger AS Fitzgerald A Yadav AR Haas FD Bushman RG Collman 《American journal of respiratory and critical care medicine》2012,186(6):536-545
Rationale: Long-term survival after lung transplantation is limited by infectious complications and by bronchiolitis obliterans syndrome (BOS), a form of chronic rejection linked in part to microbial triggers. Objectives: To define microbial populations in the respiratory tract of transplant patients comprehensively using unbiased high-density sequencing. Methods: Lung was sampled by bronchoalveolar lavage (BAL) and upper respiratory tract by oropharyngeal wash (OW). Bacterial 16S rDNA and fungal internal transcribed spacer sequencing was used to profile organisms present. Outlier analysis plots defining taxa enriched in lung relative to OW were used to identify bacteria enriched in lung against a background of oropharyngeal carryover. Measurements and Main Results: Lung transplant recipients had higher bacterial burden in BAL than control subjects, frequent appearance of dominant organisms, greater distance between communities in BAL and OW indicating more distinct populations, and decreased respiratory tract microbial richness and diversity. Fungal populations were typically dominated by Candida in both sites or by Aspergillus in BAL but not OW. 16S outlier analysis identified lung-enriched taxa indicating bacteria replicating in the lower respiratory tract. In some cases this confirmed respiratory cultures but in others revealed enrichment by anaerobic organisms or mixed outgrowth of upper respiratory flora and provided quantitative data on relative abundances of bacteria found by culture. Conclusions: Respiratory tract microbial communities in lung transplant recipients differ in structure and composition from healthy subjects. Outlier analysis can identify specific bacteria replicating in lung. These findings provide novel approaches to address the relationship between microbial communities and transplant outcome and aid in assessing lung infections. 相似文献
107.
Blumen MB Quera Salva MA Vaugier I Leroux K d'Ortho MP Barbot F Chabolle F Lofaso F 《Sleep & breathing》2012,16(3):903-907
Purpose
This study aimed to determine if the intensity of breathing noise (including snoring) and/or the presence of abnormal breathing events (ABE) are factors that trigger arousal/awakening of a snorer??s bed partner.Methods
We conducted a prospective multicenter study investigating couples where the male had a chronic disturbing snoring. We simultaneously recorded the male??s respiration and snoring and the female?? sleep. We counted the number of arousals and awakenings during N2 sleep and randomly took nine of each. Then, for periods before, during, and after each arousal and awakening, we observed on the respiratory tracings what was happening in terms of breathing noise intensity and presence/absence of snoring and/or ABE.Results
Thirteen couples were analyzed. The intensity of breathing noise and the presence/absence of snoring and/or ABE were comparable before and at initiation of arousal/awakening and between arousal and awakening. However, breathing volume intensity was lower and the presence of snoring and/or ABE was less frequent when the bed partner returned back to sleep from awakening compared to the other periods (p always <0.001).Conclusions
The intensity of breathing noise or the presence of ABE does not seem to be essential to trigger an arousal or an awakening. However, the persistence of noise or events may prolong the duration of wakefulness during the sleep period and could be one factor that explains the bothersome snoring. 相似文献108.
109.
François Durand Philippe Berthelot Celine Cazorla Frederic Farizon Frederic Lucht 《International orthopaedics》2013,37(4):723-727
Purpose
In recent guidelines, smoking is reported as a factor increasing the risk of surgical site infection (SSI). The accurate analysis of the literature shows that this recommendation relies on low level of evidence in orthopaedic surgery with material implantation (arthroplasty components or implants for internal fixation). This study aimed to assess the attributable risk of smoking on organ/space SSI in orthopaedic surgery with implants.Methods
Risk factors of organ/space SSI were studied in a prospective cohort including 3,908 patients from June 2003 to December 2006.Results
Smoking was found as a significant risk factor for organ/space SSI. We also observed a significant difference between smokers and non-smokers for surgical wound complications (hematoma, discharge or wound dehiscence) during the period between surgical procedure and discharge from hospital.Conclusion
This is the first large prospective report of a significant association between smoking and organ/space SSI in orthopaedic surgery with implants. 相似文献110.
Frederic Mercier Tina M. Weatherby Daniel K. Hartline 《The Journal of comparative neurology》2013,521(4):760-790
Meninges, the connective tissue of the vertebrate central nervous system (CNS), have not been recognized in invertebrates. We describe the ultrastructure of the adult brain, antennules, and cord in five marine copepods: Calanus finmarchicus, Gaussia princeps, Bestiolina similis, Labidocera madurae, and Euchaeta rimana. In all of these locations we identified cell types with characteristics of the typical cells of vertebrate meninges and of their peripheral nervous system (PNS) connective tissue counterpart: fibroblasts, having flattened twisting processes with labyrinthine cavities communicating with the extracellular space, and macrophages, containing prominent lysosomes, well‐developed endoplasmic reticulum, Golgi apparatus, and indented heterochromatin. The vertebrate distinction between electron‐dense cells in the most external connective tissues (dura mater and epineurium) versus electron‐lucent cells in the more internal connective tissues (pia‐arachnoid and endoneurium‐perineurium) was also found in the copepod CNS and PNS. Similar to the vertebrate organization, electron‐dense cell networks penetrated from the outer layer (subcuticle) to surround inner substructures of the copepod nervous systems, and electron‐lucent networks penetrated deeply from the brain and nerve surfaces to form intertwined associations with neural cells. Moreover, the association of these cells with basement membranes, glycocalyx, and fibrils of collagen in copepods conforms to a meningeal organization. The primary deviation from the vertebrate ultrastructural organization was the often tight investment of axons by the meningeal‐like cells, with an intercalated basement membrane. Together, these data suggest that the tissues investing the copepod nervous system possess an organization that is analogous in many respects to that of vertebrate meninges. J. Comp. Neurol. 521:760–790, 2013. © 2012 Wiley Periodicals, Inc. 相似文献