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Aims: The aim of this study is to investigate the effect of mitral stenosis (MS) on left atrial (LA) function using two‐dimensional speckle tracking echocardiography (2DSTE). Methods and Results: The study subjects consisted of 52 patients with asymptomatic MS and 52 control subjects. LA function was assessed using prototype speckle tracking software and manual tracking method. Maximal LA volume (LAVmax) and minimal LA volume (LAVmin) and LA volume before atrial contraction (LAVpre‐a) were measured. Using these volumes, LA reservoir, conduit and booster pump fuction parameters were calculated. Indexed LAVmax, LAVmin, and LAVpre‐a measurements via speckle tracking were highly correlated with manual tracing methods in both groups. Expansion index (67.8 ± 36.4 vs. 148.3 ± 44.2), diastolic emptying index (37.7 ± 12.9 vs. 58.0 ± 8.5), passive emptying (37.3 ± 14.1 vs. 70.4 ± 10.4) and passive emptying index (13.3 ± 6.3 vs. 41.3 ± 10.6) were decreased significantly in MS patients (P < 0.001). In contrast active emptying index (62.6 ± 4.1 vs. 29.5 ± 10.1) increased in MS group (P < 0.001) while active emptying (28.1 ± 13.0 vs. 28.3 ± 6.9) remained same among both groups. Conclusions: This is the first study relating LA volumes and function assessed by 2DSTE to MS. 2D speckle tracking analysis of LA volume is relatively easy and provides more detailed information regarding the changes in LA volumes during the cardiac cycle.  相似文献   
103.
Nonsmall cell lung cancer (NSCLC) is the most common type of lung cancer and remains the deadliest form of cancer in the United States and worldwide. New therapies are highly sought after to improve outcome. The effect of sodium-R-alpha lipoate on camptothecin- and paclitaxel-induced cytotoxicity was evaluated on A549 NSCLC and BEAS-2B “normal” lung epithelial cells. Combination indices (CI) and dose reduction indices (DRI) were investigated by studying the cytotoxicity of sodium-R-alpha lipoate (0–16 mM), camptothecin (0–25 nM) and paclitaxel (0–0.06 nM) alone and in combination. 3-(4,5-dimethylthiazol-2-Yl)-2,5-diphenyltetrazolium-bromide (MTT) was used to assess cytotoxicity. The combinational cytotoxic effects of sodium-R-alpha lipoate with camptothecin or paclitaxel were analyzed using a simulation of dose effects (CompuSyn® 3.01). The effects of sodium-R-alpha lipoate on camptothecin- and paclitaxel-induced cytotoxicity varied based on concentrations and treatment times. It was found that sodium-R-alpha lipoate wasn't cytotoxic toward BEAS-2B cells at any of the concentrations tested. For A549 cells, CIs [(additive (CI = 1); synergistic (CI < 1); antagonistic (CI < 1)] were lower and DRIs were higher for the camptothecin/sodium-R-alpha-lipoate combination (CI = ~0.17–1.5; DRI = ~2.2–22.6) than the paclitaxel/sodium-R-alpha-lipoate combination (CI = ~0.8–9.9; DRI = ~0.10–5.8) suggesting that the camptothecin regimen was synergistic and that the addition of sodium-R-alpha lipoate was important for reducing the camptothecin dose and potential for adverse effects.  相似文献   
104.
ObjectivesTo study the potential factors include gene mutation, efflux pump and alteration of permeability associated with quinolone-resistance of Salmonella enterica strains isolated from patients with acute gastroenteritis and to evaluate the degree of synergistic activity of efflux pump inhibitors when combined with ciprofloxacin against resistant isolates.MethodsAntimicrobial resistance patterns of fifty-eight Salmonella isolates were tested. Five isolates were selected to study the mechanism of resistance associated with quinolone group, including mutation in topoisomerase-encoding gene, altered cell permeability, and expression of an active efflux system. In addition, the combination between antibiotics and efflux pump inhibitors to overcome the microbial resistance was evaluated.ResultsFive Salmonella isolates totally resistant to all quinolones were studied. All isolates showed alterations in outer membrane proteins including disappearance of some or all of these proteins (Omp-A, Omp-C, Omp-D and Omp-F). Minimum inhibitory concentration values of ciprofloxacin were determined in the presence/absence of the efflux pump inhibitors: carbonyl cyanide m-chlorophenylhydrazone, norepinephrin and trimethoprim. Minimum inhibitory concentration values for two of the isolates were 2–4 fold lower with the addition of efflux pump inhibitors. All five Salmonella isolates were amplified for gyrA and parC genes and only two isolates were sequenced. S. Enteritidis 22 had double mutations at codon 83 and 87 in addition to three mutations at parC at codons 67, 76 and 80 whereas S. Typhimurium 57 had three mutations at codons 83, 87 and 119, but no mutations at parC.ConclusionsEfflux pump inhibitors may inhibit the major AcrAB-TolC in Salmonella efflux systems which are the major efflux pumps responsible for multidrug resistance in Gram-negative clinical isolates.  相似文献   
105.
Phoma sabdariffae is the main roselle pathogenic fungus agent in Gabon. The present study was undertaken in order to experiment a biological strategy to eradicate this pathology. Hence, spice and ginger essential oils were extracted (rotavapor) and incorporated in PDA medium, constituting 3 concentrated (1/4, 1/2 and 3/4) samples. Fungus growth was measured after culture with a gradual ruler. The results showed all spice and ginger extracts inhibited significantly Phoma sabdariffae mycelium growth. Fungus inhibition rates were proportional to plant extracts’ concentrations. But for a same concentration the effects between the 2 plants’ essential oils weren’t different. Hence, the use of spice- and ginger-concentrated crude extracts may be envisaged against Phoma sabdariffae pathogenic agent.  相似文献   
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107.
We introduce a novel in vivo model of human mucosal immunity, based on the implantation of human fetal bronchial mucosa and autologous peribronchial lymph node (PLN) in the severe combined immunodeficiency (SCID) mouse. In the SCID host, human fetal bronchi implanted alone retain macrophages and mast cells but lose T cells. In contrast, fetal bronchi co-implanted with PLN contain, in addition to macrophages and mast cells, numerous T cells and B cells, often clustered in intramucosal bronchus-associated lymphoid tissue (BALT). Functionally, bronchus-PLN cografts are able to mount robust alphabeta and gammadelta T-cell-mediated immune responses to Pseudomonas aeruginosa and 3,4-epoxy-3-methyl-1-butyl-diphosphate challenges. No other autologous lymphoid organ (bone marrow, thymus, liver) allows for BALT development in co-implanted bronchi, which suggests special ontogenetic and functional relations between extramucosal PLN and intramucosal BALT. Overall, the bronchus-PLN cograft appears as a promising model for human bronchial immune development and function. Our study is the first to document long-term ex vivo maintenance of functional human lymph nodes as native appendices to mucosal tissue. Our results, therefore, suggest a simple strategy for developing similar experimental models of human immune function in other mucosae.  相似文献   
108.
109.
Objectives:To assess National Institutes of Health Stroke Scale (NIHSS), stroke volume, biochemical, and blood parameters for the prediction of one-month mortality in stroke patientsMethods:The study had retrospective design and 75 patients were involved that presented to a hospital Emergency Department between January 2016 and December 2017 in Adiyaman, Turkey diagnosed with acute ischemic cerebral infarction. The patients were divided into 2 groups according to whether mortality occurred within one month. Values for NIHSS, stroke volume, Glasgow Coma Scale, and blood parameters were compared between the groups.Results:Values for Glasgow Coma Scale p=0.002, NIHSS p=0.001, stroke volume p=0.003, monocyte/HDL ratio p=0.047, neutrophils p=0.01, white blood cell p=0.007, calcium p=0.016, and albumin p=0.027 were statistically significant for the prediction of one-month mortality. There were no significant differences between the groups for other parameters.Conclusion:The clinical, laboratory, and radiological findings individually provide significant support for the short-term prognosis of stroke. The evaluation of these results together can provide a clearer advance understanding of a prognosis to better manage the course of the disease and prevent death.

Stroke is the third most common cause of death for patients presenting to emergency departments worldwide.1 Thus, to foresee possible mortality and morbidity in stroke cases, adoption of the right treatment and follow-up approach is important.2 The quality of the health service in a hospital emergency department depends on the successful prediction of the course of the disease and the clinical picture that may arise. Being aware of the prognosis of the disease in advance is important not only for making optimal treatment decisions but also for correctly informing the patient and managing health expenditures.In the literature, clinical parameters such as C reactive protein (CRP), red cell distribution width (RDW), neutrophil/lymphocyte ratio, and routine blood parameters such as albumin, infarct volume on admission, and National Institutes of Health Stroke Scale (NIHSS) score have previously been defined for the prediction of mortality in stroke cases.2-5 Pro-brain natriuretic peptides and pro-atrial natriuretic peptides, 2 other biochemical parameters that are not among the routine blood parameters, have also been shown to be important markers of stroke prognosis.6,7This study aimed to evaluate the association of clinical, biochemical, and radiological parameters with one-month mortality in patients that presented to the emergency service and received a diagnosis of ischemic stroke.  相似文献   
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