Assessment of aldehyde dehydrogenase in viable cells

Cytosolic aldehyde dehydrogenase (ALDH), an enzyme responsible for oxidizing intracellular aldehydes, has an important role in ethanol, vitamin A, and cyclophosphamide metabolism. High expression of this enzyme in primitive stem cells from multiple tissues, including bone marrow and intestine, appears to be an important mechanism by which these cells are resistant to cyclophosphamide. However, although hematopoietic stem cells (HSC) express high levels of cytosolic ALDH, isolating viable HSC by their ALDH expression has not been possible because ALDH is an intracellular protein. We found that a fluorescent aldehyde, dansyl aminoacetaldehyde (DAAA), could be used in flow cytometry experiments to isolate viable mouse and human cells based on their ALDH content. The level of dansyl fluorescence exhibited by cells after incubation with DAAA paralleled cytosolic ALDH levels determined by Western blotting and the sensitivity of the cells to cyclophosphamide. Moreover, DAAA appeared to be a more sensitive means of assessing cytosolic ALDH levels than Western blotting. Bone marrow progenitors treated with DAAA proliferated normally. Furthermore, marrow cells expressing high levels of dansyl fluorescence after incubation with DAAA were enriched for hematopoietic progenitors. The ability to isolate viable cells that express high levels of cytosolic ALDH could be an important component of methodology for identifying and purifying HSC and for studying cyclophosphamide-resistant tumor cell populations.     

Patient blood management in orthopaedic surgery: a four-year follow-up of transfusion requirements and blood loss from 2008 to 2011 at the Balgrist University Hospital in Zurich,Switzerland

Background

The aim of this study was to investigate the impact of the introduction of a Patient Blood Management (PBM) programme in elective orthopaedic surgery on immediate pre-operative anaemia, red blood cell (RBC) mass loss, and transfusion.

Materials and methods

Orthopaedic operations (hip, n=3,062; knee, n=2,953; and spine, n=2,856) performed between 2008 and 2011 were analysed. Period 1 (2008), was before the introduction of the PBM programme and period 2 (2009 to 2011) the time after its introduction. Immediate pre-operative anaemia, RBC mass loss, and transfusion rates in the two periods were compared.

Results

In hip surgery, the percentage of patients with immediate pre-operative anaemia decreased from 17.6% to 12.9% (p<0.001) and RBC mass loss was unchanged, being 626±434 vs 635±450 mL (p=0.974). Transfusion rate was significantly reduced from 21.8% to 15.7% (p<0.001). The number of RBC units transfused remained unchanged (p=0.761). In knee surgery the prevalence of immediate pre-operative anaemia decreased from 15.5% to 7.8% (p<0.001) and RBC mass loss reduced from 573±355 to 476±365 mL (p<0.001). The transfusion rate dropped from 19.3% to 4.9% (p<0.001). RBC transfusions decreased from 0.53±1.27 to 0.16±0.90 units (p<0.001). In spine surgery the prevalence of immediate pre-operative anaemia remained unchanged (p=0.113), RBC mass loss dropped from 551±421 to 404±337 mL (p<0.001), the transfusion rate was reduced from 18.6 to 8.6% (p<0.001) and RBC transfusions decreased from 0.66±1.80 to 0.22±0.89 units (p=0.008).

Discussion

Detection and treatment of pre-operative anaemia, meticulous surgical technique, optimal surgical blood-saving techniques, and standardised transfusion triggers in the context of PBM programme resulted in a lower incidence of immediate pre-operative anaemia, reduction in RBC mass loss, and a lower transfusion rate.     

Synergistic effect of aqueous extract of Telfaria occidentalis on the biological activities of artesunate in Plasmodium berghei infected mice

Background

Resistance to most antimalarial drugs has encouraged the use of herbal preparations along with prescribed orthodox drugs.

Objective

To investigate effect of co-administration of aqueous extract of T. occidentalis leaves; commonly used as antimalarial and haematinic agent in Nigeria and artesunate using P. berghei animal model.

Methods

In vivo curative antiplasmodial effect of T. occidentalis (200mg/kg) alone and combination with artesunate (2mg/kg) were evaluated using albino mice infected with 10⁶ parasitized erythrocytes of P. berghei intraperitoneally. The haematological parameters: haemoglobin level, red blood cells and white blood cells and packed cell volume were monitored using standard methods.

Results

Aqueous extract of T. occidentalis, artesunate and the combination gave 72.17±4.07%, 70.43± 4.27% and 85.43±3.65% reduction in parasitaemia after 48hours respectively. A significant enhancement of the PCV was obtained with the coadministration of artesunate and aqueous extract (p< 0.01). Similar trends were also observed with heamatological parameters at 72hours of administration.

Conclusion

This study revealed a synergistic effect of the co-administration on parasite clearance rate of P. berghei infection in mice, with a significant enhancement of haematological parameters within 48 hours of administration. This indicates a rapid rate of recovery from plasmodial infections with the co-administration.     

Off-pump surgery for the poor ventricle?

Severely decreased ejection-fraction is an established risk-factor for worse outcome after cardiac surgery. We compare outcomes of off-pump coronary artery bypass grafting (OPCAB) and on-pump CABG (ONCABG) in patients with severely compromised EF. From 2004 to 2009, 478 patients with a decreased EF ??35% underwent myocardial-revascularization. Patients received either OPCAB (n?=?256) or ONCABG (n?=?222). Propensity score (PS), including 50 preoperative risk-factors, was used to balance characteristics between groups. PS adjusted logistic regression analysis was performed to assess mortality and major adverse cardiac and cerebrovascular events (MACCE). A composite endpoint for major non-cardiac complications such as respiratory failure, renal failure, rethoracotomy was applied. Complete revascularization (CR) was assumed when the number of distal anastomoses was larger than that of diseased vessels. There was no difference for mortality (2.3 vs. 4.1%; PS-adjusted odds ratio (PS-OR)?=?1.05; p?=?0.93) and MACCE (13.7 vs. 17.6%; PS-OR?=?1.22; p?=?0.50) including myocardial-infarction (1.4 vs. 4.9%; PS-OR?=?0.39; p?=?0.26), low cardiac output (2.3 vs. 4.7%; PS-OR?=?0.75; p?=?0.72) and stroke (2.3 vs. 2.7%; PS-OR?=?0.69; p?=?0.66). OPCAB patients presented with a trend to less frequent occurrence of the non-cardiac composite (12.1 vs. 22.1%; PS-OR?=?0.54; p?=?0.059) including renal dysfunction (PAOR?=?0.77; 95% CI 0.31?C1.9; p?=?0.57), bleeding (PAOR?=?0.42; 95% CI 0.14?C1.20; p?=?0.10) and respiratory failure (PAOR?=?0.39; 95% CI 0.05?C3.29; p?=?0.39). The rate of complete revascularization was similar (92.2 vs. 92.8%; PS-OR?=?0.75; p?=?0.50). OPCAB in patients with severely decreased EF is safe and feasible. It may even benefit these patients in regard to non-cardiac complications and does not come at cost of less complete revascularization.     

Osteosarcoma: use of MR imaging and MR spectroscopy in clinical decision making

Magnetic resonance (MR) imaging was performed on 14 patients with histologically proved osteosarcoma (mean age, 14.4 years). There was excellent correlation of intramedullary tumor extent as determined with MR imaging and pathologic examination (r = 99%). This was facilitated by the presence of a chemical shift artifact at the tumor-marrow interface on the T1-weighted images. The correlation between CT and pathologic findings was not as good (r = 84%). In a single patient, however, a 10-cm length of sclerotic bone was incorrectly interpreted as being tumor. If this case is excluded, the correlation between CT and pathologic findings improves significantly (r = 96%). T2-weighted images were optimal in demonstrating soft-tissue bulk and breach of the epiphysis or cortex. Vascular involvement was also readily defined. The T2 value of the tumor soft-tissue component decreased in patients who were deemed to have responded well to therapy. Two patients with very high T2 values after chemotherapy developed wide-spread metastatic disease and died. Phosphorus-31 MR spectroscopy of five patients with osteosarcoma showed elevated levels of phosphomonoesters (PMEs), inorganic phosphate (Pi), and phosphodiesters (PDEs). PME and PDE peak areas decreased in three patients after chemotherapy, while Pi peak areas increased.     

Ankle: surface coil MR imaging at 1.5 T

High-field surface coil magnetic resonance (MR) images were obtained of 12 ankles: two from healthy volunteers, seven from patients, and three from fresh cadavers. The cadaver ankles were sectioned in the coronal, sagittal, and axial planes for direct comparison with the MR images. Plain film confirmation of pathologic conditions was obtained in all patients, and five underwent arthroscopy or surgery, or both. MR imaging provided excellent delineation of ligaments and cartilaginous structures in all cases.     

Occupational voice demands and their impact on the call-centre industry

Background  

Within the last decade there has been a growth in the call-centre industry in the UK, with a growing awareness of the voice as an important tool for successful communication. Occupational voice problems such as occupational dysphonia, in a business which relies on healthy, effective voice as the primary professional communication tool, may threaten working ability and occupational health and safety of workers. While previous studies of telephone call-agents have reported a range of voice symptoms and functional vocal health problems, there have been no studies investigating the use and impact of vocal performance in the communication industry within the UK. This study aims to address a significant gap in the evidence-base of occupational health and safety research. The objectives of the study are: 1. to investigate the work context and vocal communication demands for call-agents; 2. to evaluate call-agents' vocal health, awareness and performance; and 3. to identify key risks and training needs for employees and employers within call-centres.     

Estimating the cost of blood: past, present, and future directions

Understanding the costs associated with blood products requires sophisticated knowledge about transfusion medicine and is attracting the attention of clinical and administrative healthcare sectors worldwide. To improve outcomes, blood usage must be optimized and expenditures controlled so that resources may be channeled toward other diagnostic, therapeutic, and technological initiatives. Estimating blood costs, however, is a complex undertaking, surpassing simple supply versus demand economics. Shrinking donor availability and application of a precautionary principle to minimize transfusion risks are factors that continue to drive the cost of blood products upward. Recognizing that historical accounting attempts to determine blood costs have varied in scope, perspective, and methodology, new approaches have been initiated to identify all potential cost elements related to blood and blood product administration. Activities are also under way to tie these elements together in a comprehensive and practical model that will be applicable to all single-donor blood products without regard to practice type (e.g., academic, private, multi- or single-center clinic). These initiatives, their rationale, importance, and future directions are described.