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991.

Background

Central line-associated bloodstream infections (CLABSIs) are among the most serious complications especially in blood cancer patients. In January 2013, Centers for Disease and Prevention (CDC) introduced a new surveillance definition of mucosal barrier injury-associated laboratory-confirmed bloodstream infection (MBI-LCBI). This study was to determine the impact of MBI-LCBI on CLABSIs and compare the clinical characteristics of MBI versus non-MBI-LCBI cases.

Patients and methods

We retrospectively reviewed the records of 250 consecutive patients. They were admitted in department of hematology at Aichi Medical University Hospital. We applied the revised 2013 CLABSI surveillance protocol to all CLABSI cases identified during the 47-months period from May 2012 through June 2016.

Results

A total of 44 CLABSIs were identified. The median patient age was 65 years (range, 12 to 89). Among 44 patients, 31 patients were diagnosed as leukemia (70.5%) and 12 patients as lymphoma (27.3%). Six patients underwent bone transplantation for leukemia or myelodysplastic syndrome (13.6%). A total of 20 patients (45.5%) were classified as MBI-LCBI and 24 (54.5%) were classified as non-MBI-LCBI. The primary disease type (P = 0.018), neutropenic within 3 days before CLABSI (MBI-LCBI vs. non-MBI-LCBI: 95.0% vs. 26.3%, P = <0.0001), line(s) removed owing to CLABSI (15.0% vs. 54.2%, P = 0.011) and Gram-negative organisms cultured (70.0% vs. 37.5%, P = 0.004) showed significantly difference between the groups.

Conclusion

Our data showed that MBI-LCBI cases account for 45.5% of the CLABSI cases identified in blood cancer patients, and constituted a significant burden to this high-risk patient population.  相似文献   
992.
Leukapheresis is like any other preparative apheresis, except it isn’t: Leukapheresis typically takes much longer, larger blood volumes are processed and, consequently, larger ACD-A volumes are administered. Blood component donors and leukapheresis subjects are also quite different populations. Allogeneic donors tend to be younger and many are first-time donors, both of which are risk factors for adverse reactions during blood donation. Moreover, more than half of all leukapheresis collections are performed in patients. Here it is the age distribution, including patients at the extremes of age, as well as the underlying disease and co-morbidities which may expose them to higher, or different, risks compared to donors. Both groups thus have good reasons why adverse effects to leukapheresis might be more frequent, more severe, or even different in nature altogether. Compared to other preparative apheresis types like platelet or plasma apheresis, the risks of leukapheresis have been studied less extensively, as it is in comparison a relatively low-frequency intervention. Often leukapheresis remains a domain of hematologists who have a different sense of procedural safety than transfusionists. Furthermore, G-CSF mobilized “stem cell” aphereses by a wide margin outnumber unmobilized aphereses, so that the very strong signal from adverse reactions to G-CSF all but drowns out signals from the apheresis proper. This focused review assesses observations from leukapheresis as well as extrapolation of observations from other forms of preparative apheresis in an attempt to gauge the safety of leukapheresis and identify potential approaches to its further improvement. In short, the overall impression is one of a very satisfactory safety record of leukapheresis, with occasional issues with venous access or vasovagal problems, and frequent, but highly responsive and rarely limiting ACD-A toxicity.  相似文献   
993.

Background

Extended phenotyping is one of the important method of reducing red cell alloimmunisation. Extended phenotyping of red cells from voluntary donors have many uses in addition to its application in population genetics. As there was very little data extended phenotyping on a cohort of Indian Voluntary blood donors this project was undertaken.

Study design & methodology

200 regular voluntary blood donors having ‘O’ blood group were included for red cell antigen typing of Rh (D,C,E,c,e), Kell (K, k, Kpa, Kpb), Duffy (Fya, Fyb), Kidd (Jka, Jkb), Lewis(Lea, Leb), P(P1), MNS (M, N,S,s), and Lutheran (Lua, Lub), Colton (Coa, Cob), Diago (Diaa, Wra), Vw and Xga antigens using conventional antisera provided by DIAGAST. Calculations of antigen and phenotypes frequencies were expressed as percentages.

Results

Out of 200 ‘O’ group blood donors, 96.5% were Rh D and 2.5% were K positive. Amongst Rh antigens, e was the most common (100%) followed by D, C (91.0%), c (50.5%) and E (16.5%) with DCe/DCe (R1R1, 48.0%) being the most common phenotype. In Kell blood group system, we found k antigen to be 100% and a rare phenotype Kp (a?+?b+) was found in 1% of the donors. For Kidd and Duffy blood group systems, Jk (a?+?b+) and Fy (a?+?b-) were the most common phenotypes (39.0% and 64.0%, respectively). In the MNS blood group system, M?+?N+ (67.5%) and S?+?s+(43.5%) were the most common phenotypes. There were antigens like Cw(3.5%), K(2.3%), Kpa(1.2%), Ina(1.0%), Vw(1.2%), Coa(4.5%), Cob(1%), Lua(1.75%), Dia+(1.2%), and Wra+(0.6%) with frequency < 5% in the donor population.

Conclusion

Extensively antigen phenotypes group ‘O’ red cells showed significant variation with other population from India as well as with Caucasian and black population. Extensive phenotyping ‘O’ group regular blood donors of red cell antigens is very useful to prepare in-house red cell panels for identification of alloantibodies.  相似文献   
994.
995.

Introduction

Evidence suggests that red cell antigens may act as receptors for viruses and bacteria and therefore could be associated with HIV infection. Previous studies have been controversial and therefore the aim of this exploratory study was to analyse the expression of immunogenic red cell antigens in HIV-seropositive individuals and to compare the results to negative donors from South Africa.

Methods

The expression of ABO, Rh, Kell and Duffy antigens from 119 HIV-seropositive patients was compared to 317 HIV-seronegative blood donors. Nucleic acid amplification testing and PCR were used to determine the HIV status and the ID-Gel Card Technology was used to determine the blood group antigen profile.

Results

There was no significant difference in the expression of A, B, AB, Duffy or Kel antigens between the two groups but significantly lower numbers of HIV+ individuals were O Rh Negative (p?=?,0.0001). Analysis of those with a Duffy null phenotype revealed a significantly higher incidence of blood type A RH1-Positive, Dce/R0r and B RH1-Positive, DcEe/R2r within the HIV-seropositive group (p?=?<?0.05). None of the HIV-seropositive individuals were O RH1-Negative, dce/rr.

Conclusion

In conclusion these initial findings have demonstrated a decreased incidence of blood type O Rh1-negative in HIV?+?individuals which suggests that red blood cell antigens may play an important role in susceptibility to HIV infection. The relationship between red cell antigens and HIV infection however remains complex and therefore larger studies are required to confirm these results.  相似文献   
996.

Background

Fluid shifts from interstitial to intravascular space during blood donation helps in compensating the lost blood volume. We aimed to determine the volume of fluid shift following donation in donors with and without pre-donation fluid intake.

Methods

We studied the fluid shift in 325 blood donors prospectively. Donors were divided in groups- with no fluid intake (GI) and either water (GII) or oral rehydrating fluids (GIII) before donation. Fluid shift following donation was calculated based on the difference between the pre and post donation blood volume. The influence of oral fluid intake, age, gender and body mass index (BMI) on volume of fluid shift was analyzed.

Results

The fluid shift was significant between donors without fluids (GI: 127?±?81?ml) and donors with fluid intake (GII & III: 96?±?45?ml) (p?<?0.05). The difference was not significant between donors with water intake (GII: 106?±?52?ml) and oral rehydrating fluid intake (GIII: 87?±?41?ml). The shifted fluid volume increased with increasing BMI and decreased with increasing age in females. The fluid shift increased in females than in males.

Conclusion

The age, gender, BMI and VVR did not significantly contribute to the volume of fluid shift following donation. As per our observation, the oral fluids before donation might not contribute to increase in fluid shift in blood donors after donation.  相似文献   
997.
Introduction: The antimicrobial aspect of management of patients with blood stream infections (BSI) and sepsis is time critical. In an era of increasing antimicrobial resistance, rapid detection and identification of bacteria with antimicrobial susceptibility is crucial to direct therapy early in the course of illness. Molecular techniques offer a potential solution to this.

Areas covered: In the present review the authors have discussed a number of novel solutions utilizing a variety of molecular techniques for pathogen detection, identification and antimicrobial susceptibility. The review is not designed to be an exhaustive literature review covering all diagnostic solutions ever developed, instead the authors have focused on what they have had experience using, evaluating or currently view as new and exciting with potential to revolutionize BSI diagnosis.

The authors searched PubMed (Medline) and Google Scholar with terms: BSI, Bacteraemia, Candidaemia, Diagnostics, AST, Rapid, AMR, Novel and Blood Culture. The authors attended recent clinical microbiology technology congresses.

Expert commentary: There are multiple exciting novel technologies at differing stages of development with potential to revolutionize diagnosis of BSI. More work is needed as well as a standardized assessment of different platforms in order to better understand the clinical and financial impacts these will have in clinical microbiology laboratories.  相似文献   

998.

Background

Preoperative anemia and allogeneic blood transfusions (ABTs) may affect outcomes in cancer surgery. The prevalence of anemia, the use of ABTs, the risks of transfusions, lengths of stay and mortality of oncological patients undergoing radical cystectomy were investigated in three University Hospitals in Germany.

Patients and Methods

Hospital records of 220 consecutive patients undergoing radical cystectomy from 2010 to 2012 were retrospectively analyzed for independent risk factors of ABT and unfavorable outcomes (readmission, increased length of stay (LOS) or death) using multivariate regression analysis.

Results

Preoperative anemia was present in 40%. 70% of patients received blood transfusions. Low preoperative and intraoperative nadir hemoglobin levels were associated with receipt of ABT (OR 1.33, P?=?0.04 and OR 2.94, P?<?0.001 respectively). Transfusion of ten or more red blood cell units (RBCs) during the entire hospital stay was a predictor of an increased LOS (P?<?0.001) and death (OR 52, 95%CI [5.9, 461.3], P?<?0.001), compared to non-transfused patients. Preoperative ABT and ASA scores were associated with ≥10RBCs.

Conclusion

Anemic patients undergoing radical cystectomy had a high risk to receive ABTs. Preoperative transfusions and transfusion of ≥10RBCs during the entire hospital stay may increase patient`s mortality.Prospective, randomized controlled studies have to follow this study.  相似文献   
999.
郭霞珍教授认为肝脾肾三脏的功能失调与青春期崩漏的发生关系密切,如肝郁血热、脾虚失摄、肾精不足等。无论何种原因导致的崩漏,血出日久,或过用固涩药物止血,最终均可发展为血瘀。故临床治疗应以活血化瘀以澄其源,同时针对"瘀"形成的不同原因,佐以疏肝清热、健脾益气或补肾填精,方能取得预期疗效。  相似文献   
1000.
目的 探索制备一种新型的耦连包载BDNF脂质体纳米颗粒的脂膜微泡超声造影剂(BDNF-UMCA)。方法 以冷冻干燥法在“脂氟显”制备的基础上加入一定比例的含生物素化棕榈酰磷脂酰甘油钠-聚乙二醇2000-生物素[DPPG-PEG(2000)-Biotin]制备含生物素的脂质超声微泡造影剂,通过链亲和素来耦连含生物素化PEG载BDNF脂质体纳米微粒制备BDNF-UMCA,检测其理化性质、载药量、包封率、稳定性和体内声学特性进行检测。结果 BDNF-UMCA平均粒径4.2±0.79 μm,浓度为1.02×109/ml;总药物含量为1.18±1.96 mg/mL,包封率为71.6±2.6%;BDNF-UMCA在4℃条件下,平均粒径和包封率均无明显的变化;在24℃条件下,载BDNF脂质体纳米微粒的平均粒径随时间逐渐增大,第1、3、5、7天的粒径与初始粒径比较具有明显的统计学差异(均P<0.05),包封率在24℃下各个时间点无明显的统计学差异(均P>0.05);BDNF-UMCA能显著增强实验动物肝脏显影,平均峰值强度为21.4±0.9 dB,平均达峰时间为4.7±0.4 s。结论 应用生物素-亲和素偶联可成功制备载BDNF脂质体纳米微粒的脂膜超声微泡造影剂,为靶向显影及药物通过血脑屏障释放提供工具。  相似文献   
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