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51.
Because information on management and outcome of AML relapse after allogeneic hematopoietic stem cell transplantation (HSCT) with reduced intensity conditioning (RIC) is scarce, a retrospective registry study was performed by the Acute Leukemia Working Party of EBMT. Among 2815 RIC transplants performed for AML in complete remission (CR) between 1999 and 2008, cumulative incidence of relapse was 32% ± 1%. Relapsed patients (263) were included into a detailed analysis of risk factors for overall survival (OS) and building of a prognostic score. CR was reinduced in 32%; remission duration after transplantation was the only prognostic factor for response (P = .003). Estimated 2-year OS from relapse was 14%, thereby resembling results of AML relapse after standard conditioning. Among variables available at the time of relapse, remission after HSCT > 5 months (hazard ratio [HR] = 0.50, 95% confidence interval [CI], 0.37-0.67, P < .001), bone marrow blasts less than 27% (HR = 0.53, 95% CI, 0.40-0.72, P < .001), and absence of acute GVHD after HSCT (HR = 0.67, 95% CI, 0.49-0.93, P = .017) were associated with better OS. Based on these factors, 3 prognostic groups could be discriminated, showing OS of 32% ± 7%, 19% ± 4%, and 4% ± 2% at 2 years (P < .0001). Long-term survival was achieved almost exclusively after successful induction of CR by cytoreductive therapy, followed either by donor lymphocyte infusion or second HSCT for consolidation.  相似文献   
52.
There is controversy with regard to the entry pathway of the rabies virus (RABV) into the central nervous system (CNS). Some authors have suggested that the virus inoculated at the periphery is captured and transported to CNS only by motor neurons; however, it has been reported that dorsal root ganglia (DRG) sensory neurons capture and transport the virus to the spinal cord (SC) and then to the brain. It is probable that preferences for one pathway or another depend on the site of inoculation and the post-infection time. Therefore, in the present study, we evaluated different vertebral segments and post-infection times, along with the location, number, and subpopulation of sensory neurons susceptible to infection after inoculating RABV in the footpads of adult mice. It was noted that the virus inoculated in the footpad preferentially entered the CNS through the large-sized DRG sensory neurons, while infection of the motor neurons occurred later. Further, it was found that the virus was dispersed in spinal cord trans-synaptically through the interneurons, arriving at both sensory neurons and contralateral motor neurons. In conclusion, we observed that RABV inoculated in the plantar footpad is captured preferentially by large sensory neurons and is transported to the DRG, where it replicates and is spread to the SC using transynaptic jumps, infecting sensory and motor neurons at the same level before ascending to the brain.  相似文献   
53.

Background

Perioperative short-term outcomes could be improved after totally robotic Roux-en-Y gastric bypass (TR-RYGBP) compared with conventional laparoscopic gastric bypass.

Methods

This is a nonrandomized controlled prospective study (N = 200) to evaluate perioperative short-term outcomes. The primary endpoint was to investigate risk factors for 30-day surgical complications.

Results

Mean total operative time was shorter in patients who underwent TR-RYGBP (130 vs 147 minutes; P < .0001). However, postoperative surgical complications rate (13% vs 1%; P = .001), and mean overall hospital stay (9.3 vs 6.7 days; P < .0001) were higher after TR-RYGBP. By multivariate analysis, robotic surgery (hazard ratio [HR] = 15.1; 95% confidence interval [CI], 2.8 to 280; P = .01), and conversion to laparotomy (HR = 18.8; 95% CI, 1.7 to 250.8; P = .014) were independent risk factors for 30-day surgical complications.

Conclusions

Although robotic gastric bypass reduces mean operative time, TR-RYGBP is associated with an increased postoperative surgical complications rate and longer hospitalization.  相似文献   
54.

BACKGROUND:

Patients with upper gastrointestinal bleeding (UGIB) require an early, tailored approach best guided by knowledge of the bleeding lesion, especially a variceal versus a nonvariceal source.

OBJECTIVE:

To identify, by investigating a large national registry, variables that would be predictive of a variceal origin of UGIB using clinical parameters before endoscopic evaluation.

METHODS:

A retrospective study was conducted in 21 Canadian hospitals during the period from January 2004 until the end of May 2005. Consecutive charts for hospitalized patients with a primary or secondary discharge diagnosis of UGIB were reviewed. Data regarding demographics, including historical, physical examination, initial laboratory investigations, endoscopic and pharmacological therapies administered, as well as clinical outcomes, were collected. Multivariable logistic regression modelling was performed to identify clinical predictors of a variceal source of bleeding.

RESULTS:

The patient population included 2020 patients (mean [± SD] age 66.3±16.4 years; 38.4% female). Overall, 215 (10.6%) were found to be bleeding from upper gastrointestinal varices. Among 26 patient characteristics, variables predicting a variceal source of bleeding included history of liver disease (OR 6.36 [95% CI 3.59 to 11.3]), excessive alcohol use (OR 2.28 [95% CI 1.37 to 3.77]), hematemesis (OR 2.65 [95% CI 1.61 to 4.36]), hematochezia (OR 3.02 [95% CI 1.46 to 6.22]) and stigmata of chronic liver disease (OR 2.49 [95% CI 1.46 to 4.25]). Patients treated with antithrombotic therapy were more likely to experience other causes of hemorrhage (OR 0.44 [95% CI 0.35 to 0.78]).

CONCLUSION:

Presenting historical and physical examination data, and initial laboratory tests carry significant predictive ability in discriminating variceal versus nonvariceal sources of bleeding.  相似文献   
55.

BACKGROUND:

Discrepancies exist in reported mortality rates of nonvariceal upper gastrointestinal bleeding (NVUGIB).

OBJECTIVE:

To perform a systematic review assessing possible reasons for these disparate findings and to more reliably compare them.

METHODS:

The MEDLINE, EMBASE and ISI Web of Knowledge databases were searched for studies reporting mortality rates in NVUGIB involving adults and published in English. To ensure robust and contemporary estimates, studies spanning 1996 to January 2011 that included more than 1000 patients were selected.

RESULTS:

Eighteen of 3077 studies were selected. Ten studies used administrative databases and the remaining eight used registries. The mortality rates reported in these studies ranged from 1.1% in Japan to 11% in Denmark. There were variations in reported mortality rates among countries and also within countries. Reasons for these disparities included a spectrum of quality in reporting as well as heterogeneous definitions of case ascertainment, differing patient populations with regard to severity of presentation and associated comorbidities, varying durations of follow-up and different health care system-related practices.

CONCLUSIONS:

Wide differences in reported NVUGIB mortality rates are attributable to differences in adopted methodologies and populations studied. More uniform standards in reporting are needed; only then can true observed variations enable a better understanding of causes of death and pave the way to improved patient outcomes.  相似文献   
56.
To test tipranavir (TPV) or darunavir (DRV) as treatment options for patients with phenotypic resistance to protease inhibitors (PIs), including lopinavir, saquinavir, atazanavir, and fosamprenavir, the PhenoSense GT database was analyzed for susceptibility to DRV or TPV among PI-resistant isolates. The Monogram Biosciences HIV database (South San Francisco, CA) containing 7775 clinical isolates (2006-2008) not susceptible to at least one first-generation PI was analyzed. Phenotypic responses [resistant (R), partially susceptible (PS), or susceptible (S)] were defined by upper and lower clinical cut-offs to each PI. Genotypes were screened for amino acid substitutions associated with TPV-R/DRV-S and TPV-S/DRV-R phenotypes. In all, 4.9% (378) of isolates were resistant to all six PIs and 31.0% (2407) were resistant to none. Among isolates resistant to all four first-generation PIs, DRV resistance increased from 21.2% to 41.9% from 2006 to 2008, respectively, and resistance to TPV remained steady (53.9 to 57.3%, respectively). Higher prevalence substitutions in DRV-S/TPV-R isolates versus DRV-R/TPV-S isolates, respectively, were 82L/T (44.4% vs. 0%) and 83D (5.8% vs. 0%). Higher prevalence substitutions in DRV-R/TPV-S virus were 50V (0.0% vs. 28.9%), 54L (1.0% vs. 36.1%), and 76V (0.4% vs. 15.5%). Mutations to help predict discordant susceptibility to DRV and TPV in isolates with reduced susceptibility to other PIs were identified. DRV resistance mutations associated with improved virologic response to TPV were more prevalent in DRV-R/TPV-S isolates. TPV resistance mutations were more prevalent in TPV-R and DRV-S isolates. These results confirm the impact of genotype on phenotype, illustrating how HIV genotype and phenotype data assist regimen optimization.  相似文献   
57.
Flavohemoglobins (fHbs) are heme proteins found in prokaryotic and eukaryotic microbes. They are involved in NO detoxification through an NO˙ dioxygenase mechanism. The N-terminal heme globin domain allows for binding of gaseous ligands whereas a C-terminal NADH/FADH binding domain facilitates association of redox cofactors necessary for ligand reduction. The NO˙ dioxygenase function is important in facilitating immune resistance by protecting the cell from nitrosative stress brought about by a host organism; as a result, bacterial flavoHbs have recently been considered as targets for the development of new antibiotics. Here, photoacoustic calorimetry and transient absorption spectroscopy have been used to characterize energetics, structural dynamics, and kinetics of CO migration within bacterial flavoHbs from Ralstonia eutropha (FHP) and Staphylococcus aureus (HMPSa) in the presence and absence of antibiotic azole compounds. In FHP, the ligand photo-release is associated with ΔH = 26.2 ± 7.0 kcal mol−1 and ΔV = 25.0 ± 1.5 mL mol−1 while in HMPSa, ΔH = 34.7 ± 8.0 kcal mol−1 and ΔV = 28.6 ± 17 mL mol−1 were observed, suggesting distinct structural changes associated with ligand escape from FHP and HMPSa. In the presence of ketoconazole, the CO escape leads to a more negative enthalpy change and volume change whereas association of miconazole to FHP or HMPSa does not impact the reaction volume. These data are in agreement with the computational results that propose distinct binding sites for ketoconazole and miconazole on CO bound FHP. Miconazole or ketoconazole binding to either protein has only a negligible impact on the CO association rates, indicating that azole drugs do not impact flavoHbs interactions with gaseous ligands but may inhibit the NOD activity through preventing the electron transfer between FAD and heme cofactors.

Impact of ketoconalzole and miconazole on structural dynamics of flavohemoglobin.  相似文献   
58.
59.
While research to date has been successful in quantifying postural behaviour, this paper examines the causes of transition between postural coordination mode using dynamical variables and, by inference, efficient control strategies underlying postural behaviour. To this end, six subjects in bipedal stance were instructed to maintain a constant distance between their head and a visual target that oscillated along the line of sight. Within sessions, participants were exposed to gradual changes in increasing target motion frequency. Kinematic results showed a sudden transition between in-phase and anti-phase postural coordination modes in visual target tracking. The dynamical analysis pointed out that (1) the center of pressure (CoP) position parameter is a crucial parameter in the determination of the adopted coordination mode, (2) the change occurred in response to limits bordered by the system: the interaction between equilibrium constraints (A/P displacements of CoP), physiological limits (net joint moments) support the emergence of different postural behaviours and, (3) finally, the anti-phase mode presents a better distribution of muscular moment between hip and ankle joints and is more effective to achieve high frequency oscillations with limited CoP displacements.  相似文献   
60.
Background

Evidence-based policy measures need non-interest-guided information about the health status of a population and the diseases that affect the population the most. In such cases, a national burden of disease study can provide reliable insights at the regional level.

Aim

This article presents the potential of the BURDEN 2020 project and its expected outcome for Germany at the national and regional level.

Methods

The BURDEN 2020 project uses several indicators including years of life lost (YLL) to cover the impact of mortality and years lived with disability (YLD) to cover morbidity. The sum of both is the measure of population health called disability adjusted life years (DALY).

Results

The study ranks individual diseases and risk factors based on their impact on population health. The burden of disease approach is assumed to be sensitive to subnational differences and may generate immediate benefits for regional planning. The BURDEN 2020 study will pilot a national burden of disease study for Germany that will later be transformed into a continuous data processing and visualization tool. This is done by using, modifying and supplementing the methodology employed by the Global Burden of Disease (GBD) study to better fit the needs of health policy in Germany. This study is aimed at calculating the disease burden for up to 17 preselected diseases. Furthermore, the estimates of burden of disease are attributed to a selected set of risk factors.

Conclusion

The Burden 2020 study will provide the results of a new, health-related data processing system to the public. This includes a noninterest-guided presentation of the burden of disease (DALY) in Germany at the national and regional level.

  相似文献   
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