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101.
Elimination of neoplastic B cell populations from autologous bone marrow grafts also removes normal B lymphocytes. This is potentially hazardous for the reconstitution of the immune system in patients undergoing high-dose chemotherapy and total body irradiation followed by autologous marrow rescue. Five pediatric patients with B cell non- Hodgkin's lymphoma in first remission undergoing such a regimen were studied. They received bone marrow pretreated with anti-Y 29/55 monoclonal antibody and complement. B and T lymphocyte subpopulations reached normal levels within 6 months after autologous bone marrow transplantation (ABMT), and serum immunoglobulin levels became normal within 4 to 9 months. Vaccination with diphtheria and tetanus toxoid, trivalent poliomyelitis vaccine of the Salk type, and pneumococcal capsular antigens (38 to 54 months after transplantation) gave rise to specific antibody production. ABO isoagglutinins could be demonstrated in all patients. The response pattern was similar to that of patients who received unmanipulated autologous bone marrow. It is concluded that ex vivo anti-Y 29/55 depletion of the marrow graft does not induce relevant disturbances of humoral immune functions.  相似文献   
102.
It has long been established that advanced age is not only associated with greater myocardial infarction frequency but also greater mortality and morbidity. The treatment of acute myocardial infarction (AMI) in 80 year old patients remains problematic with conflicting results; in these patients, the risks of conservative treatment are high and the risks and benefits of thrombolytic therapy are still controversial. The purpose of this study was to evaluate whether primary angioplasty can offer an important alternative method to improve short- and long-term outcomes in octogenarian or older patients who experience AMI. Between May 1986 and March 2000, 171 consecutive 80 year old patients hospitalized for AMI were not randomized to be registered and divided into a medical therapy group (group 1: an historical control group, n=11) and a primary angioplasty group (group 2, n=60). In-hospital mortality was markedly increased with advanced Killip scores (Killip 3 or 4) in both groups. Twenty-four hours after admission, group 1 patients had a significantly higher incidence of progression to higher Killip scores than did group 2 patients (P=0.006). The 30-day overall mortality of group 2 patients was significantly lower than in group 1 patients (30.0% vs 54.1%, P=0.003). Patients without cardiogenic shock treated by primary angioplasty had a significantly lower incidence of overall mortality at 30 days than patients without cardiogenic shock treated conservatively [3.1% vs 24.3%, P=0.016 (Killip 1 and 2); 18.2% vs 52.6%, P=0.044 (Killip 3)]. However, the mortality rate of cardiogenic shock was extremely high and did not differ significantly between groups I and 2 (86.1% vs 88.2%, P=0.99). The 3-year cumulative survival rate was significantly higher in group 2 than in group 1 patients (P=0.0009). In conclusion, primary angioplasty is feasible and effective, and can improve short-and long-term mortalities in octogenarian or older patients with AMI but without cardiogenic shock.  相似文献   
103.
In 2013, a novel betacoronavirus was identified in fecal samples from dromedaries in Dubai, United Arab Emirates. Antibodies against the recombinant nucleocapsid protein of the virus, which we named dromedary camel coronavirus (DcCoV) UAE-HKU23, were detected in 52% of 59 dromedary serum samples tested. In an analysis of 3 complete DcCoV UAE-HKU23 genomes, we identified the virus as a betacoronavirus in lineage A1. The DcCoV UAE-HKU23 genome has G+C contents; a general preference for G/C in the third position of codons; a cleavage site for spike protein; and a membrane protein of similar length to that of other betacoronavirus A1 members, to which DcCoV UAE-HKU23 is phylogenetically closely related. Along with this coronavirus, viruses of at least 8 other families have been found to infect camels. Because camels have a close association with humans, continuous surveillance should be conducted to understand the potential for virus emergence in camels and for virus transmission to humans.  相似文献   
104.
Multimorbidity, defined as the presence of two or more chronic conditions, leads to a substantial public health burden. This study evaluated its association with adherence with cardiovascular medications in a Chinese population.  相似文献   
105.

Background

This study tested whether adipose-derived mesenchymal stem cells (ADMSC) embedded in platelet-rich fibrin (PRF) scaffold is superior to direct ADMSC implantation in improving left ventricular (LV) performance and reducing LV remodeling in a rat acute myocardial infarction (AMI) model of left anterior descending coronary artery (LAD) ligation.

Methods

Twenty-eight male adult Sprague Dawley rats equally divided into group 1 [sham control], group 2 (AMI only), group 3 (AMI + direct ADMSC implantation), and group 4 (AMI + PRF-embedded autologous ADMSC) were sacrificed on day 42 after AMI.

Results

LV systolic and diastolic dimensions and volumes, and infarct/fibrotic areas were highest in group 2, lowest in group 1 and significantly higher in group 3 than in group 4, whereas LV performance and LV fractional shortening exhibited a reversed pattern (p < 0.005). Protein expressions of inflammation (oxidative stress, IL-1β, MMP-9), apoptosis (mitochondrial Bax, cleaved PARP), fibrosis (Smad3, TGF-β), and pressure-overload biomarkers (BNP, MHC-β) displayed a pattern similar to that of LV dimensions, whereas anti-inflammatory (IL-10), anti-apoptotic (Bcl-2), and anti-fibrotic (Smad1/5, BMP-2) indices showed a pattern similar to that of LV performance among the four groups (all p < 0.05). Angiogenesis biomarkers at protein (CXCR4, SDF-1α, VEGF), cellular (CD31 +, CXCR4 +, SDF-1α +), and immunohistochemical (small vessels) levels, and cardiac stem cell markers (C-kit +, Sca-1 +) in infarct myocardium were highest in group 4, lowest in group 1, and significantly higher in group 3 than in group 2 (all p < 0.005).

Conclusion

PRF-embedded ADMSC is superior to direct ADMSC implantation in preserving LV function and attenuating LV remodeling.  相似文献   
106.
107.

Background

Women undergoing coronary artery bypass grafting (CABG) are at increased risk for morbidity and mortality. Factors responsible for this observation include smaller coronary size and delayed presentation. To date, no studies have examined the effect of the degree of myocardium at risk (MAR) on the relationship between female sex and adverse postoperative events.

Methods

Consecutive patients undergoing first-time isolated CABG at a single institution from 2002-2007 were identified. MAR was calculated using the weighted Duke Index and was categorized as low, moderate, or high. Multivariable logistic regression models were created to compare the impact of MAR on adverse clinical events.

Results

We identified 3741 patients, 3325 (89%) of whom had complete angiographic data. Women (n = 755) were older (P = 0.0001) and presented more often with hypertension (P = 0.0001), diabetes (P = 0.0001), heart failure (P = 0.0001), and an urgent/emergent situation (P = 0.002). After surgery, women experienced greater rates of adverse events (15.2% vs 9.3%; P = 0.0001). In a fully adjusted logistic regression model, the nested interaction of sex in MAR showed that women had a significantly greater risk of major adverse cardiovascular events (MACE) when MAR was high (odds ratio [OR], 1.9; 95% confidence interval [CI], 1.3-2.6; P = 0.0004). Greater severity of MAR emerged as an independent predictor of adverse events among women (high: OR, 2.9; 95% CI, 1.2-7.3; moderate: OR, 2.2; 95% CI, 0.8-5.7; low: OR, 1.0), but not among men.

Conclusions

MAR was independently associated with higher rates of adverse events among women but not in men undergoing CABG. This finding may help explain differences in outcomes seen between women and men after revascularization.  相似文献   
108.
Evidence is emerging that rates of adverse events in patients taking warfarin may vary with ethnicity. This study investigated the rates of bleeds and thromboembolic events, the international normalised ratio (INR) status and the relationship between INR and bleeding events in Malaysia. Patients attending INR clinic at the Heart Centre, Sarawak General Hospital were enrolled on an ad hoc basis from May 2010 and followed up for 1 year. At each routine visit, INR was recorded and screening for bleeding or thromboembolism occurred. Variables relating to INR control were used as predictors of bleeds in logistic regression models. 125 patients contributed to 140 person-years of follow-up. The rates of major bleed, thromboembolic event and minor bleed per 100 person-years of follow-up were 1.4, 0.75 and 34.3. The median time at target range calculated using the Rosendaal method was 61.6 % (IQR 44.6–74.1 %). Of the out-of-range readings, 30.0 % were below range and 15.4 % were above. INR variability, (standard deviation of individuals’ mean INR), was the best predictor of bleeding events, with an odds ratio of 3.21 (95 % CI 1.10–9.38). Low rates of both major bleeds and thromboembolic events were recorded, in addition to a substantial number of INR readings under the recommended target range. This may suggest that the recommended INR ranges may not represent the optimal warfarin intensity for this population and that a lower intensity of therapy, as observed in this cohort, could be beneficial in preventing adverse events.  相似文献   
109.
Because of their high efficiency and sharp emission, perovskite light-emitting diodes are a promising candidate for next-generation lighting techniques. However, the relatively poor stability of perovskite light-emitting diodes lowers their utility. Therefore, a highly stable perovskite light-emitting diode has to be developed to meet the commercial demand. Herein, we report a highly stable CsPbBr3 light-emitting diode via simple polymer treatment. The addition of 2-methyl-2-oxazoline in perovskite film assists the formation of CsPbBr3 nanocrystals, improving the quality and photoluminescence property of perovskite film. Based on such CsPbBr3 nanocrystals and polymer hybrid film, our device presents a high external quantum efficiency and luminance of around 3.0% and 16 648 cd m−2, respectively. Moreover, an excellent device half-lifetime of more than 2.4 hours has been achieved, under continuous operation at a relatively high initial luminance of 1000 cd m−2, representing one of the most stable PeLEDs operated at such high initial luminance.

The 2-methyl-2-oxazoline additive induced the formation of high-quality CsPbBr3 nanocrystals and a stable PeLED with a half-lifetime of 2.4 hours at high initial luminance of 1000 cd m−2 was demonstrated, representing one of the most stable PeLEDs.  相似文献   
110.
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