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51.
We retrospectively analyzed the prognostic significance of mixed chimerism and associated clinical parameters in 80 patients following unmanipulated allogenic stem cell transplantation. Chimerism studies were performed on marrow aspirates using fluorescent in situ hybridization and variable number tandem repeats techniques at day +30, day +90 and +12 months. The median overall survival (OS) was 24 months (range, 1-56 months). Mixed chimerism was found in 23, 28 and 14% of patients at day +30 (1 month), +90 (3 months), and +12 months, respectively. Day +30 chimerism studies failed to provide any prognostic information. Day +90 mixed chimeras (MC) had significantly higher relapse rates compared to day +90 complete chimeras (CC) at 6 months (P=0.03) and 18 months when compared to MC (P=0.03) following transplant. The median OS in day +90 MC and day+90 CC were, respectively (95% CI, 2-35 months), compared to 47 months (95% CI, 20-74 months) (P=0.02). In conclusion, chimerism studies on day +30 could be reserved for patients who fail to demonstrate engraftment. Day +90 MC had higher relapse rates and lower OS, and therefore may be considered for novel therapies and future studies.  相似文献   
52.
Diffuse neurological manifestations of preeclampsia are due to endothelial involvement that lead to ischemia, hemorrhage, or edema. We analyzed clinical and radiological features and the course of brainstem ischemic strokes in a preeclampsia patient. We report a case of severe preeclampsia in a 30-year-old woman who was admitted 10 hr after a vaginal delivery at home. The pregnancy was at 39 wk, with no prenatal care. At her admission, she was conscious, and she had tetraparesia, swinging deep tendon reflex testing, drowsiness, and dysarthria; the BP was at 160/100 mmHg and 4 + proteinuria; magnetic resonance imaging revealed brainstem ischemic stroke. The evolution was favorable with symptomatic treatment. The patient was discharged on the 16th day; 2 months later she had a normal recovery. Brainstem strokes are rare. They are frequently due to hemorrhage; sometimes, they can also be ischemic. Their course is favorable.  相似文献   
53.
BACKGROUND: Osteopenia of prematurity is a known source for morbidity in preterm infants. Premature infants have shown favorable outcomes in response to massage and physical activity. Whether such intervention can stimulate bone formation or decrease bone resorption is yet to be determined. OBJECTIVE: To test the hypothesis that massage combined with physical activity can stimulate bone formation and ameliorate bone resorption in premature infants. DESIGN/METHODS: A prospective double-blinded randomized trial was conducted at the Neonatal Intensive Care Unit of Ain Shams University in Cairo, Egypt. Thirty preterm infants (28 to 35 weeks' gestation) were randomly assigned to either control group (Group I, n=15) or intervention group (Group II, n=15). Infants in the intervention group received a daily protocol of combined massage and physical activity. Serum type I collagen C-terminal propeptide (PICP) and urinary pyridinoline crosslinks of collagen (Pyd) were used as indices for bone formation and resorption, respectively. PICP and Pyd were measured at enrollment and at discharge for all subjects. t-Test, ANOVA and linear regression analysis were used for statistical analyses. RESULTS: There was no difference between groups I and II in gestational age (32.1+/-1.8 vs 31.5+/-1.4 weeks) or birth weight (1.429+/-0.148 vs 1.467+/-0.132 g). In the control group, serum PICP decreased over time from 82.3+/-8.5 to 68.78+/-14.6 (p<0.01), while urinary Pyd increased from 447.7+/-282.8 to 744.9+/-373.6 (p<0.01) indicating decreased bone formation and increased bone resorption, respectively. In the intervention group, serum PICP increased over time from 62.5+/-13.8 to 73.84+/-12.9 (p<0.01). Urinary Pyd also increased over time from 445.7+/-266.5 to 716.8+/-301.8 (p<0.01). In a linear regression model including gestational age and intervention, serum PICP increased significantly in the intervention group (regression coefficient 18.8+/-4.6, p=0.0001) while urinary Pyd did not differ between groups (regression coefficient=5.6+/-114.3, p=0.961). CONCLUSIONS: A combined massage and physical activity protocol improved bone formation (PICP) but did not affect bone resorption (Pyd). Pyd increased over time in both groups, possibly due to continuous bone resorption and Ca mobilization.  相似文献   
54.
A prospective observational study was designed to evaluate the effect of the different techniques of hysterectomy on urinary and sexual function. One hundred and eighty-seven women aged 29-73 years and admitted for hysterectomy for various indications were recruited to the study. Women presenting primarily with major uterine prolapse and those requiring radical hysterectomy were excluded. Patients underwent one of four different techniques of hysterectomy: total abdominal, vaginal, laparoscopic or subtotal. All patients completed a standardised questionnaire addressing urinary and sexual symptoms and underwent urodynamic testing using the Lectromed 6000 System (Lectromed, Letchworth, Herts, UK) before and 6 months after surgery. Out of 187 women, 184 (98.4%) had completed data. Seventy-three patients (39%) had a total abdominal hysterectomy, 62 (34%) had vaginal, 38 (21%) had laparoscopic and 11 (6%) had subtotal hysterectomy. At 6 months after surgery, urinary symptoms occurred less frequently (P<0.01) and urodynamic studies remained unchanged. Moreover, patients reported significantly lower rates of stress incontinence (P=0.005), urgency (P=0.03) and deep dyspareunia (P<0.001) than before the operation, regardless of the hysterectomy technique used. The route of hysterectomy did not influence the outcome of surgery. We conclude that simple hysterectomy, whether performed abdominally, vaginally or laparoscopically, does not adversely affect urinary or sexual function at 6 months after surgery.  相似文献   
55.
BackgroundShared and divergent predictors of clinical severity across respiratory viruses may support clinical and community responses in the context of a novel respiratory pathogen.MethodsWe conducted a retrospective cohort study to identify predictors of 30‐day all‐cause mortality following hospitalization with influenza (N = 45,749; 2010‐09 to 2019‐05), respiratory syncytial virus (RSV; N = 24 345; 2010‐09 to 2019‐04), or severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2; N = 8988; 2020‐03 to 2020‐12; pre‐vaccine) using population‐based health administrative data from Ontario, Canada. Multivariable modified Poisson regression was used to assess associations between potential predictors and mortality. We compared the direction, magnitude, and confidence intervals of risk ratios to identify shared and divergent predictors of mortality.ResultsA total of 3186 (7.0%), 697 (2.9%), and 1880 (20.9%) patients died within 30 days of hospital admission with influenza, RSV, and SARS‐CoV‐2, respectively. Shared predictors of increased mortality included older age, male sex, residence in a long‐term care home, and chronic kidney disease. Positive associations between age and mortality were largest for patients with SARS‐CoV‐2. Few comorbidities were associated with mortality among patients with SARS‐CoV‐2 as compared with those with influenza or RSV.ConclusionsOur findings may help identify patients at greatest risk of illness secondary to a respiratory virus, anticipate hospital resource needs, and prioritize local prevention and therapeutic strategies to communities with higher prevalence of risk factors.  相似文献   
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Phage therapy is a promising biocontrol management on plant diseases caused by bacterial pathogens due to its specificity, efficiency and environmental friendliness. The emergence of natural phage-resistant bacteria hinders the application of phage therapy. Xanthomonas oryzae pv. oryzae (Xoo) is the causal agent of the devastating bacterial leaf blight disease of rice. Here, we obtained a spontaneous mutant C2R of an Xoo strain C2 showing strong resistance to the lytic phage X2. Analysis of the C2R genome found that the CDS2289 gene encoding glycosyltransferase acquired a frameshift mutation at the 180th nucleotide site, which also leads to a premature stop mutation at the 142nd amino acid. This mutation confers the inhibition of phage adsorption through the changes in lipopolysaccharide production and structure and bacterial surface morphology. Interestingly, glycosyltransferase-deficient C2R and an insertional mutant k2289 also showed reduced virulence, suggesting the trade-off costs of phage resistance. In summary, this study highlights the role of glycosyltransferase in interactions among pathogenic bacteria, phages and plant hosts, which provide insights into balanced coevolution from environmental perspectives.  相似文献   
59.
The fully developed laminar flow of a viscous non-Newtonian fluid in a rough-walled pipe is considered. The fluid rheology is described by the power–law model (covering shear thinning, Newtonian, and shear thickening fluids). The rough surface of the pipe is considered to be fractal, and the surface roughness is measured using surface fractal dimensions. The main focus of this study lies in the theoretical investigation of the influence of the pipe surface roughness on the velocity profile and the Darcy friction factor of an incompressible non-Newtonian fluid. The plotted results demonstrate that shear thinning fluids are the most sensitive to the surface roughness compared with Newtonian and shear thickening fluids. For a particular value of the surface fractal dimension, there exists an intersection point where shear thinning, Newtonian, and shear thickening fluids behave the same way regarding the amplitude of the velocity profile and the friction factor. This approach has a variety of potential applications, for instance fluid dynamics in hydrology, blood flow in the cardiovascular system, and many industrial applications.  相似文献   
60.
Certain anticancer agents selectively target the nucleus of cancer cells. One such drug is 2-methoxyestradiol (2ME), which is used for treating lung cancer. To improve the therapeutic effectiveness of these agents, many new methods have been devised. 2ME was entrapped into the core of hydrophobic invasomes (INVA) covered with Phospholipon 90G and apamin (APA). The Box–Behnken statistical design was implemented to enhance the composition. Using Design-Expert software (Stat-Ease Inc., Minneapolis, MN), the INVA component quantities were optimized to obtain spherical particles with the smallest size, that is, a diameter of 167.8 nm. 2ME-INVA-APA significantly inhibited A549 cells and exhibited IC50 of 1.15 ± 0.04 µg/mL, which is lower than raw 2ME (IC50 5.6 ± 0.2 µg/mL). Post 2ME-INVA-APA administration, a significant rise in cell death and necrosis was seen among the A549 cells compared to those treated with plain formula or 2ME alone. This effect was indicated by increased Bax expression and reduced Bcl-2 expression, as well as mitochondrial membrane potential loss. Moreover, the cell cycle analysis showed that 2ME-INVA-APA arrests the G2-M phase of the A549 cells. Additionally, it was observed that the micellar formulation of the drug increased the cell count in pre-G1, thereby exhibiting phenomenal apoptotic potential. Furthermore, it up-regulates caspase-9 and p53 and downregulates TNF-α and NF-κβ. Collectively, these findings showed that our optimized 2ME-INVA-APA could easily seep through the cell membrane and induce apoptosis in relatively low doses.  相似文献   
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