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1.
Vox Sang ; 98(3 Pt 1): e219-24, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20002621

ABSTRACT

BACKGROUND AND OBJECTIVES: Emergency situations often elicit a generous response from the public. This occurred after attacks on the US on September 11, 2001 when many new blood donors lined up to donate. This study was performed to compare return rates for first time donors (FTD) after September 11th, 2001 to FTD during a comparable period in 2000. MATERIALS AND METHODS: A total of 3315 allogeneic whole blood donations from FTD at a regional blood centre were collected between September 11th and 30th, 2001. Subsequent donations by the FTD before March 31, 2002 were reviewed. This (test) group was compared to 1279 FTD (control group) donating during the same time period in September 2000 and to their return rate in the subsequent 6 months. RESULTS: Following September 11, 2001, 1087/3315 (32.8%) FTD returned by March 31, 2002. This return rate was similar to the control group [427/1279 (33.4%)]. The deferral rate during the donor screening process for the control group was significantly higher than the deferral rate for the September 11-30, 2001 group (P < 0.01). The odds of an individual FTD returning increased with age, and the chance of a female donor returning was 1.13 times higher than a male (P = 0.06). There was a carryover effect after September 11, 2001 too. CONCLUSION: A national emergency, September 11, 2001, inspired people to donate blood for the first time. However, the proportion of return donations amongst them was not increased. Females and males in certain age groups were more likely to become repeat donors due to the residual effect of September 11, 2001. Additional efforts are needed to retain eligible FTD in donor pools.


Subject(s)
Blood Donors/psychology , Disasters , Motivation , Volunteers/psychology , Adult , Blood Donors/statistics & numerical data , Female , Humans , Male , Middle Aged , Terrorism , United States , Volunteers/statistics & numerical data , Young Adult
2.
Vox Sang ; 89(4): 215-9, 2005 Nov.
Article in English | MEDLINE | ID: mdl-16262754

ABSTRACT

BACKGROUND AND OBJECTIVES: Transfusion-associated graft-versus-host disease (TA-GVHD) is a serious, potential complication of blood transfusion that is essentially prevented by blood product irradiation. Blood product irradiation is currently performed using gamma irradiation. X-ray irradiation is an alternative that has certain advantages: an X-ray irradiator is less expensive and does not have a radioactive source. However, the biochemical effects of X-ray irradiation on red blood cells (RBCs) have not been well characterized. The primary purpose of our study was to compare the effects of X-ray irradiation with gamma irradiation on RBC membrane permeability. A secondary purpose was to verify that X-ray irradiation has the same effect on lymphocytes as gamma irradiation. MATERIALS AND METHODS: Ten RBC units were split into two portions; five units of each were then irradiated with either gamma or X-ray at a dose of 35 Gy or 25 Gy, respectively. Free plasma haemoglobin and extracellular potassium levels were measured in each unit over time. Another unit was divided into three parts for lymphocyte studies; one part was not irradiated as a control and the other two received 25 Gy of irradiation via X-ray or gamma irradiation, respectively. RESULTS: Minimally increased free plasma haemoglobin was found only in X-ray-irradiated units after 25 Gy compared to gamma-irradiated units. However, extracellular potassium levels were not significantly different in these groups. Extracellular potassium levels were slightly higher only in gamma irradiated units at 35 Gy. X-ray and gamma irradiation were equivalent in affecting lymphocyte function. CONCLUSIONS: Small differences in RBC membrane permeability are found between gamma-irradiated and X-ray-irradiated units. However, these differences are not likely to be clinically important.


Subject(s)
Cell Membrane Permeability/radiation effects , Erythrocyte Membrane/radiation effects , Erythrocyte Transfusion , Gamma Rays , Graft vs Host Disease/prevention & control , X-Rays , Adenine , Citrates , Dose-Response Relationship, Radiation , Glucose , Hemolysis/radiation effects , Humans , Phosphates
3.
Transfusion ; 44(7): 984-9, 2004 Jul.
Article in English | MEDLINE | ID: mdl-15225237

ABSTRACT

BACKGROUND: Blood components that appear hemolyzed are discarded. However, visual inspection is subjective and criteria for excessive hemolysis are poorly defined. STUDY DESIGN AND METHODS: Packed RBCs (10 CPDA-1, 10 Adsol) were collected. Half of each unit was leukoreduced. Plasma Hb was measured and compared in segments and units by three methods: 1) a HemoCue Plasma/Low Hb Photometer system; 2) a tetramethyl-benzidine (TMB) chemical method, and 3) a free Hb visual comparator. RESULTS: Visual assessment tended to overestimate hemolysis. Chemical methods were comparable (r(2)= 0.894; HemoCue = 0.043 +[0.770]x TMB; n = 400; range, 0.01-0.5 g/dL), although the mean plasma Hb (g/dL) for the HemoCue method was higher than that of the TMB method (0.12 vs. 0.10 g/dL, respectively; p < 0.001). No units would have been discarded based on a hemolysis level of at least 0.6 g/dL (approx. 1%) if measured by a chemical method. However, 50 percent of CPDA-1 and 10 percent of Adsol units would have been discarded if only visual criteria were used. Leukoreduction did not increase plasma Hb levels. Discrepancies in plasma Hb levels were noted between units and their corresponding segments. CONCLUSION: Visual assessment of hemolysis can result in unnecessary wastage of blood components. HemoCue offers an alternative, objective method to assess plasma Hb in the setting of blood collection and processing facilities for routine quality control and process validation, and may aid in the development of objective criteria for excessive hemolysis in blood components.


Subject(s)
Erythrocyte Transfusion , Hemoglobins/analysis , Hemolysis , Anticoagulants/pharmacology , Blood Preservation , Humans
4.
Vox Sang ; 86(1): 48-53, 2004 Jan.
Article in English | MEDLINE | ID: mdl-14984560

ABSTRACT

BACKGROUND AND OBJECTIVES: Platelet function abnormalities have been reported in blood donors who have not consumed aspirin. Our objective was to identify factors other than aspirin that may contribute to impaired platelet function in qualified volunteer blood donors. MATERIALS AND METHODS: Blood samples were obtained from 24 donors following routine blood donation. Donors completed a study questionnaire that included questions about recent food consumption, medication and medical history. Platelet activation was measured using monoclonal antibodies and flow cytometry. CD62P expression and PAC-1 binding on platelets were used as indicators of platelet activation. Platelet function was measured on a platelet function analyser (PFA-100) using both collagen/epinephrine (cEPI) and collagen/ADP (cADP) cartridges. RESULTS: Fifty-four per cent of donors (13 of 24) had normal platelet function. Thirty-eight per cent (nine of 24) had prolonged cEPI closure times, of whom four (17%) had no cEPI closure (> 300 seconds). No closure was associated with aspirin use (two donors) or chocolate consumption (two donors) before donation. Two donors (8%) had either a shortened cEPI or cADP closure time. CONCLUSIONS: Platelet dysfunction in qualified blood donors is underestimated. Platelet function screening can identify donors with diet-related platelet dysfunction or with poor recollection of aspirin use.


Subject(s)
Blood Donors , Blood Transfusion/standards , Platelet Activation , Adult , Aged , Aspirin/pharmacology , Cacao/adverse effects , Female , Food/adverse effects , Humans , Male , Middle Aged , Platelet Function Tests , Surveys and Questionnaires
5.
Cytometry ; 50(5): 254-60, 2002 Oct 15.
Article in English | MEDLINE | ID: mdl-12360575

ABSTRACT

BACKGROUND: Universal leukoreduction of blood components is becoming the standard of care. Flow cytometry methods are being used for quality control of the leukoreduction process. METHODS: We provide an atlas of atypical flow cytograms generated by a commercial LeucoCOUNT assay that was used to enumerate residual leukocytes in leukoreduced red blood cell components. Numeric results are derived from a flow cytogram generated by the assay. RESULTS: Three types of atypical flow cytogram patterns were observed during process validation or routine quality control of leukoreduced red blood cell components. (a) Fixation artifact: Fixation of control or test samples can alter the staining intensity compared with fresh cells. (b) "Rain" pattern: Flow cytometry methods count slightly damaged leukocytes not removed during leukoreduction. Slightly damaged leukocytes appear on a flow cytogram like "rain" falling from a well-defined "cloud" of intact residual leukocytes. Discrepancies between automated flow cytometry results and subjective manual counting methods can occur. (c) Autofluorescence-debris pattern: Cell debris and age-related changes in the sample can cause shifts in the fluorescence staining pattern, resulting in erroneous test results. CONCLUSION: Review of flow cytograms is essential for accurate reporting of flow cytometry-based methods for enumerating residual leukocytes in leukoreduced blood components.


Subject(s)
Artifacts , Cell Count/methods , Cell Separation/methods , Erythrocyte Transfusion/methods , Flow Cytometry/methods , Leukocytes/cytology , Leukocytes/immunology , Erythrocyte Transfusion/adverse effects , Humans , Quality Control , Reproducibility of Results , Software
6.
Indian J Pediatr ; 68(2): 159-65, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11284185

ABSTRACT

Increasingly complicated surgeries are being performed on neonatal and pediatric patients. Provision of a safe and adequate blood supply is essential for the success of many of these surgeries. Depending on the clinical situation, autologous and/or allogeneic blood may be used. However, in all cases, every attempt should be made to minimize the number of donor exposures to reduce the risk of transfusion transmitted infections. Transfusion of neonatal and pediatric patients requires additional considerations too, such as the risk of graft vs host disease, cytomegalovirus infection, the effects of various preservative anticoagulant solutions, electrolyte levels during blood storage, and wheather or not leukoreduced components are indicated.


Subject(s)
Blood Loss, Surgical , Blood Transfusion/methods , Intraoperative Care/methods , Blood Donors , Child , Cytomegalovirus Infections/etiology , Cytomegalovirus Infections/prevention & control , Graft vs Host Disease/prevention & control , Hemodilution , Humans , Infant, Newborn , Transfusion Reaction
7.
Arch Pathol Lab Med ; 122(3): 266-72, 1998 Mar.
Article in English | MEDLINE | ID: mdl-9823867

ABSTRACT

BACKGROUND: Tumors of the pancreas with osteoclast-like giant cells are of uncertain histogenesis and aggressiveness. Their relationship, if any, to undifferentiated (anaplastic) carcinomas of the pancreas with pleomorphic giant cells is also not clear. METHODS: Eleven tumors with osteoclast-like giant cells were studied by immunohistochemistry for epithelial and mesenchymal markers, as well as for a proliferation marker (Ki67) and p53 protein expression. Cytometric image analysis for nuclear DNA content was also performed. K-ras mutations were investigated by DNA sequence analysis. RESULTS: Neoplastic, predominantly spindle-shaped cells and osteoclast-like giant cells were positive for mesenchymal markers CD68, LCA, and A1ACT. These spindle-shaped cells were also positive for human muscle actin. Spindle-shaped cells of seven tumors were also positive for epithelial markers carcinoembryonic antigen, epithelial membrane antigen, or keratin. Nine tumors contained a variable number of pleomorphic giant cells in addition to osteoclast-like giant cells. Pleomorphic giant cells were much less positive for mesenchymal markers than were osteoclast-like giant cells, but they were positive for some epithelial markers. A high percentage of spindle-shaped and pleomorphic giant cells were positive for Ki67. Diploid and aneuploid populations were present in varying proportions in both spindle cells and pleomorphic giant cells. The nuclei of osteoclast-like giant cells, however, were diploid and not proliferating. Spindle-shaped and pleomorphic giant cells were positive for p53 protein in 5 of 10 cases. Five of six tumors studied were positive for K-ras mutations. CONCLUSION: The distinction between tumors with osteoclast-like giant cells and undifferentiated carcinomas with pleomorphic giant cells is often not clear-cut. Both types of tumors have mesenchymal and epithelial characteristics in varying proportions and may arise from an undifferentiated pancreatic stem cell. Long-term survival of two patients suggests that some tumors with osteoclast-like giant cells may have a better prognosis than the usual pancreatic ductal adenocarcinoma.


Subject(s)
Giant Cells/pathology , Osteoclasts/pathology , Pancreatic Neoplasms/pathology , Cell Division/physiology , Genes, ras/genetics , Humans , Immunohistochemistry , Ki-67 Antigen/analysis , Mutation/genetics , Pancreatic Neoplasms/chemistry , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/immunology , Ploidies , Tumor Suppressor Protein p53/analysis
9.
Ann Plast Surg ; 36(3): 297-303, 1996 Mar.
Article in English | MEDLINE | ID: mdl-8659955

ABSTRACT

Various centers report irradiated cartilage graft absorption rates that differ quite widely. We postulated that a major factor governing this phenomenon might be irradiation dose. Irradiation produces collagen cross-binding and increased resistance to absorption of such material when implanted. Since cross-binding produces stiffening of collagen, cartilage grafts were exposed to increasing doses of irradiation and their elastic modulus was measured. The postulate was that increasing radiation doses will produce grafts of increasing stiffness. Sternal cartilage, harvested from horses, was cut into blocks of a standard size and irradiated to 4, 6, 8, and 10 megarads. The elastic modulus of each specimen and matched control were measured on an Instron flexural testing machine (Instron Corp, Canton, MA). Irradiation at all four doses reduced the elastic modulus of the cartilage grafts, with the lowest dose producing a reduction of 50% and the highest dose one of 90%. High-dose irradiation appears to lessen greatly the stiffness of cartilage grafts and may be responsible for increasing absorption of grafts in centers in which high doses are used.


Subject(s)
Cartilage/radiation effects , Radiation Injuries, Experimental/pathology , Absorption , Animals , Cartilage/pathology , Cartilage/transplantation , Dose-Response Relationship, Radiation , Elasticity , Horses
10.
Urology ; 43(2): 203-8, 1994 Feb.
Article in English | MEDLINE | ID: mdl-8116116

ABSTRACT

OBJECTIVE: To determine the efficacy of the vaginal wall sling in the management of recurrent stress urinary incontinence (SUI) in an elderly female population. METHOD: Eighteen elderly female patients (average age 68.4 years) with recurrent stress urinary incontinence were studied with a thorough evaluation including video-urodynamics. Thirteen patients were diagnosed with type III SUI and 5 patients had type II SUI: A description of the technique, first described by Raz, is provided. RESULTS: Follow-up ranged from six to forty-two months (average 18 months). All patients are completely dry and express satisfaction with their outcome. Seventeen of 18 patients (94%) are voiding spontaneously. One patient at twelve months' postoperation requires clean intermittent catheterization. CONCLUSION: Many elderly female patients with recurrent stress urinary incontinence have intrinsic urethral sphincteric incompetence as well as recurrent hypermobility that often classifies them as type II SUI: The vaginal wall sling addresses both problems and is a safe, simple, and effective procedure in the management of recurrent incontinence in elderly female patients.


Subject(s)
Urinary Incontinence, Stress/surgery , Vagina/surgery , Aged , Female , Follow-Up Studies , Humans , Patient Satisfaction , Recurrence , Suture Techniques , Time Factors , Urethra/physiopathology , Urinary Catheterization , Urinary Incontinence, Stress/epidemiology , Urinary Incontinence, Stress/prevention & control
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