bluuebunny/crossref_metadata_2025_split huggingface dataset:
Plasma Homocysteine and Cognitive Impairment in an Older British African‐Caribbean Population
Authors: Stewart Robert , Asonganyi Belinda , Sherwood Roy 
Published: March 2003

OBJECTIVES: To investigate the association between homocysteine concentrations and cognitive impairment in an older African‐Caribbean population. To investigate other measures of risk for vascular disease and nutritional status as potential confounding factors.DESIGN: A secondary analysis from a cross‐sectional community study.SETTING: The sample was drawn from registration lists for seven primary care services in south London, United Kingdom.PARTICIPANTS: Two hundred forty‐eight individuals aged 55 to 75 who were born in a Caribbean nation and for whom homocysteine concentrations had been ascertained.MEASUREMENTS: Plasma homocysteine and serum folate were assayed from frozen samples. Cognitive impairment as a composite measure was derived from 11 psychometric tests. Other measures of risk for vascular disease were considered as potential confounding factors: diagnosed hypertension/diabetes mellitus; physical exercise; and concentrations of cholesterol, triglycerides, and fibrinogen.RESULTS: Cognitive impairment was classified in 68 (27%) participants. Raised homocysteine (highest quartile: >13.85 μmol/L) was significantly associated with cognitive impairment (odds ratio (OR) = 2.50, 95% confidence interval (CI) = 1.33–4.69). This association persisted after adjustment for age, occupation, other measures of vascular risk, folate, body mass index, and waist:hip ratio (OR = 3.00, 95% CI = 1.35–6.69). As with other risk factors for vascular disease in this sample, the association was significant only in those with less education (P‐value for interaction = .049).CONCLUSION: Raised homocysteine was associated with cognitive impairment in this sample, but this was modified by previous educational attainment. This association was independent of other measures of vascular risk and was not explained by folate concentrations.
Patients with Hip Fracture: Subgroups and Their Outcomes
Authors: Eastwood Elizabeth A. , Magaziner Jay , Wang Jason , Silberzweig Stacey B. , Hannan Edward L. , Strauss Elton , Siu Albert L. 
Published: March 2003

OBJECTIVES: To present several alternative approaches to describing the range and functional outcomes of patients with hip fracture.DESIGN: Prospective study with concurrent medical records data collection and patient and proxy interviews at the time of hospitalization and 6 months later.SETTING: Four hospitals in the New York metropolitan area.PARTICIPANTS: Five hundred seventy‐one hospitalized adults aged 50 and older with hip fracture between July 1997 and August 1998.MEASUREMENTS: Rates of return to function in four physical domains, mortality, and nursing home residence at 6 months. Cluster analysis was used to describe the heterogeneity among the sample and identify variations in 6‐month mortality, nursing home residence, and level of functioning and to develop a patient classification tree with associated patient outcomes at 6 months postfracture.RESULTS: In locomotion, transfers, and self‐care, 33% to 37% of patients returned to their prior level of function by 6 months, including those needing assistance, but only 24% were independent in locomotion at 6 months. Cluster analysis identified eight patient subgroups that had distinct baseline features and variable outcomes at 6 months. The patient classification tree used four variables: atypical functional status (independent in locomotion but dependent in other domains); nursing home residence; independence/dependence in self‐care; and age younger than 85 or 85 and older that identified five subgroups with variable 6‐month outcomes that clinicians may use to predict likely outcomes for their patients.CONCLUSION: Patients with hip fracture are heterogeneous with respect to baseline and outcome characteristics. Clinicians may be better able to give patients and caregivers information on expected outcomes based on presenting characteristics used in the classification tree.
Dying of Old Age: An Examination of Death Certificates of Minnesota Centenarians
Authors: Gessert Charles E. , Elliott Barbara A. , Haller Irina V. 
Published: March 2003

OBJECTIVES: To compare how causes of death are recorded on the death certificates of centenarians with those who die in their 70s, 80s, and 90s. We also examined direct and indirect acknowledgment of age as a cause of death.DESIGN: Retrospective review of death certificates.SETTING: State of Minnesota.PARTICIPANTS: The death certificates of 26,415 individuals aged 70 and over who died in Minnesota in 1998 were examined for underlying causes of death. Of these, 449 were for individuals who were aged 100 and older at the time of their death.MEASUREMENTS: Causes of death.RESULTS: Diabetes mellitus, chronic obstructive pulmonary disease, cirrhosis, myocardial infarction, and most cancers decreased in frequency as reported causes of death with advancing age. Conversely, congestive heart failure, atherosclerosis, and neurological/mental and poorly defined conditions increased in frequency with age.CONCLUSIONS: Centenarians appear to “outlive” the risks for many of the conditions that are common causes of death for those who die in their 70s, 80s, and 90s, such as cancer and myocardial infarction. Conditions associated with aging, such as congestive heart failure and degenerative neurological conditions become more prominent as reported causes of death in the oldest individuals. The guidelines for the completion of death certificates should be modified to facilitate direct acknowledgment of age‐related frailty as a contributing cause of death.
Calcium homeostasis during therapeutic plasma exchange
Authors: SILberstein L. E. , Naryshkin S. , Haddad J. J. , Strauss J. F. 
Published: March 2003

Because the removal of substantial quantities of plasma calcium during plasma exchange is rarely attended by clinically significant hypocalcemia, we evaluated calcium homeostasis during this procedure. Twenty‐one procedures were performed on 10 patients with various neurological disorders. The reduction by plasma exchange in the serum concentrations of total calcium, ionized calcium, magnesium, and phosphate was significantly less than predicted (p < 0.001) based on plasma volume of the patient and size of the exchange. However, N‐terminal parathomone (PTH) levels increased to 242 ± 120 percent midway into the procedure and were 207 ± 84 percent after plasma exchange; urinary cyclic adenosine monophosphate (cAMP) levels rose by 165 ± 35 percent.These data demonstrate a rapid compensatory response in N‐terminal PTH and urinary cAMP to the reduction by plasma exchange of serum concentrations of total calcium, ionized calcium, and phosphate. The routine administration of supplemental calcium during plasma exchange may therefore be unnecessary in patients with normal parathyroid function.
Freezing of plasma and recovery of factor VIII
Authors: Carlebjörk G. , Blombäck M. , Pihlstedt P. 
Published: March 2003

The freezing procedure and its influence on the plasma quality was studied with a new plasma container and freezing bath and compared with the results from those obtained with commonly used equipment. Cryoprecipitation was performed on plasma pools frozen at three different rates, and quality and recovery of the cryoprecipitates were determined by analysis of factor VIII, factor VIII‐related antigen (vWF:Ag), and fibrinogen. The plasma freezing time was 95 and 65 percent shorter with a new – 40°C freezing bath as compared to –25 and –80°C freezing boxes, respectively. A further 30 percent reduction of the plasma freezing time was gained by the introduction of a new flat 750‐ml plasma container. Rapid plasma freezing prevented substantial loss of factor VIII in frozen plasma. Cryoprecipitate purity measured as factor VIII‐to‐fibrinogen ratio increased from 0.50 to 0.82 (IU/mg) when the freezing time was decreased from 10 hours to 45 minutes, although the recovery of factor VIII increased less.In summary, freezing of plasma in small flat containers in an effective ethanol bath resulted in rapid freezing with high recovery of factor VIII in plasma, and increased purity and recovery of subsequently processed cryoprecipitate. This freezing concept, adapted at Swedish blood banks, has contributed to higher source plasma quality and increased self‐sufficiency.
Reappraisal of optimal hemoglobin standards for female blood donors in Canada
Authors: Pi D.W. , Krikler S.H. , Sparling T.G. , Carter C.J. , Wadsworth LD 
Published: March 2003

BACKGROUND: A hemoglobin (Hb) standard of 115 g per L on the copper sulfate test has been in use by the Canadian Red Cross Society Blood Services for female blood donor predonation screening since 1989.STUDY DESIGN AND METHODS: To determine if this lowered Hb standard results in increased iron deficiency in repeat blood donors, a study was conducted to evaluate the performance of the copper sulfate test and predonation capillary and venous Hb assays in a population of female blood donors most at risk of developing iron deficiency.RESULTS: Of the 174 donors who were of childbearing age, who were not taking iron supplements, and who had made at least three blood donations per year, 45 (25.9%) were iron deficient, and 64 (36.8%) had reduced iron stores; only 65 (37.3%) had normal iron stores. This study showed that capillary blood is more likely to have a higher Hb concentration (3.2 +/− 7.8 g/L) than venous blood samples, which could affect the performance of predonation screening assays that are based on capillary blood samples at a given discriminating value. With an Hb standard of 115 g per L, both the copper sulfate and capillary Hb assays were not sensitive enough to screen for iron deficiency (sensitivity, 27% and 33%; specificity, 96% and 93%, respectively) and were comparable only to the performance of a venous Hb assay with a cutoff value of 110 g per L (sensitivity, 27%; specificity, 99%). In contrast, an Hb standard of 125 g per L in the copper sulfate test could achieve a more optimal sensitivity of 79 percent and specificity of 78 percent.CONCLUSION: This study supports the use of a higher Hb cutoff value of 125 g per L for female blood donors in the predonation fingerstick copper sulfate test.
Red cell autoantibody production in utero: a case report
Authors: Erler B.S. , Smith L. , McQuiston D. , Pepkowitz S.H. , Goldfinger D. 
Published: March 2003

BACKGROUND: Autoantibody production by the fetus is thought to be extremely unlikely. Only one possible case of in utero autoantibody production against red cells by the fetus has previously been described.STUDY DESIGN AND METHODS: A case of apparent red cell IgG autoantibody production in utero is reported.RESULTS: This was established by a positive direct antiglobulin test in a newborn infant without evidence of maternal alloantibodies or autoantibodies. There was no evidence of clinically significant hemolysis at the infant's birth. After 6 weeks, his direct antiglobulin test remained strongly positive. The infant thrived without evidence of hemolysis, and after 6 months the direct antiglobulin test was negative.CONCLUSION: The production of autoantibodies to red cells in utero is possible, though rare. This did not result in apparent hemolysis in this patient.
Hepatitis C viral markers in patients who received blood that was positive for hepatitis C virus core antibody, with genetic evidence of hepatitis C virus transmission
Authors: Watanabe M. , Ohkoshi S. , Tawaraya H. , Miyajima T. , Shimotohno K. , Kamimura T. , Asakuar H. 
Published: March 2003

Background: Despite the use of the anti‐c100‐3 assay for blood donor screening, posttransfusion non‐A,non‐B hepatitis still occurred. A more sensitive assay should be developed to prevent this.Study Design and Methods: Stored serum specimens from 2020 healthy blood donors who were negative for c100‐3 antibody to hepatitis C virus (HCV) were retrospectively screened for the presence of antibodies against a core protein of HCV using an enzyme‐linked immunosorbent assay and Western blot analysis as part of a study on posttransfusion non‐A,non‐B hepatitis.Results: Eight (0.4%) of the 2020 donors were positive for HCV core antibody. Posttransfusion non‐A,non‐B hepatitis occurred in 5 of five patients known to have received blood that was positive for HCV core antibody and 1 of 141 patients transfused with blood that was negative for HCV core antibody. The total incidence of posttransfusion non‐A,non‐B hepatitis was 4.1 percent (6/146). The nucleotide sequence of the nonstructural 5 region of the HCV genome obtained from two donors and corresponding recipients was also analyzed. The HCV genome sequences were identical for one donor‐recipient pair, and there was 99.4‐percent homology for a second pair.Conclusion: Anti‐core‐positive blood proved to be highly infectious for HCV, and this validated the use of the second‐generation anti‐HCV assay for blood donor screening.
A survey of the incidence of Miltenberger antibodies among Hong Kong Chinese blood donors
Authors: Mak K.H. , Banks J.A. , Lubenko A. , Chua K.M. , de Jardine A.L. Torres , Yan K.F. 
Published: March 2003

Background: The ready availability of red cells of the Miltenberger (Mi) class III phenotype (6.28%) prompted the study of Mi antibodies among Chinese blood donors in Hong Kong, 98 percent of whom are descended from inhabitants of Guangdong Province in southern China.Study Design and Methods: Red cells of the Mi class III phenotype were used to conduct a survey of the frequency of Miltenberger antibodies in 56,161 random Chinese blood donors, over a period of 12 months, using a microplate technique.Results: Sera from 32 donors (0.057%) were found to contain Mi antibodies: sera from 22 contained anti‐Mur + Hut; sera from 4 contained anti‐Vw + Mur + Hut; sera from 4 had monospecific anti‐ Mur; and sera from 2 had monospecific anti‐Hil. The immunoglobulin isotypes of 24 sera were mixtures of IgM and IgG, 4 were pure IgM, and 4 were pure IgG.Conclusion: The majority of Mi antibodies detected were naturally occurring. This survey proved useful for mass screening of random donors for the procurement of valuable Mi antisera.
Effect of freezing on the in vivo recovery of irradiated red cells
Authors: MIRAGLIA C.C. , ANDERSON G. , MINTZ P.D. 
Published: March 2003

BACKGROUND: Transfusion‐associated graft‐versus‐host disease can be prevented by gamma radiation of blood components. The increased use of blood components donated for patients by their family members has resulted in an increased demand for the storage and handling of irradiated units, and the ability to freeze the cells would allow storage beyond their current expiration date.STUDY DESIGN AND METHODS: To assess the effect of freezing and deglycerolization on irradiated red cells, studies of autologous radiolabeled red cell recovery were performed using normal volunteers. Each unit of CPDA‐1 red cells was immediately divided into two equal volumes. Further handling of each half was identical except that one was irradiated (3500 cGy). The units were grouped under three protocols: I, irradiated on Day 0 and frozen on Day 5 (n = 4); II, irradiated on Day 7, rejuvenated, and frozen on Day 14 (n = 5); and III, irradiated on Day 14, rejuvenated, and frozen on Day 18 (n = 3). All cells were frozen for 3 to 10 months at −80 degrees C.RESULTS: Irradiated and control units showed no significant differences in supernatant potassium or hemoglobin. Autologous 24‐hour posttransfusion recoveries (mean +/− SD) for the three groups were: I, 89.7 +/− 5.6 percent (control, 90.6 +/− 3.2%); II, 85.3 +/− 5.7 percent (control, 83.7 +/− 3.0%); and III, 79.5 +/− 1.4 percent (control, 82.6 +/− 5.2%). CONCLUSION: Irradiated red cells can be frozen after being stored under various conditions and can still meet established guidelines requiring 75‐percent recovery 24 hours after transfusion.
Collection and transfusion of blood and blood components in the United States, 1992
Authors: Wallace E.L. , Churchill W.H. , Surgenor D.M. , An J. , Cho G. , McGurk S. , Murphy L. 
Published: March 2003

BACKGROUND: Studies were conducted to measure the state of the United States' national blood resource in 1992 and changes therein from 1989.STUDY DESIGN AND METHODS: With data supplied by the American Red Cross and the American Association of Blood Banks, as well as data from a stratified random‐sample survey of 3350 non‐American Association of Blood Banks hospitals, statistical methods were applied to estimate national blood activities in 1992.RESULTS: The total US blood supply in 1992 was 13,794,000 units, a decrease of 3.1 percent from 1989. Some 11,307,000 red cell units were transfused to 3,772,000 patients, an average of 3.0 units per transfused patient. Preoperative autologous blood deposits totaled 1,117,000 units, a 70‐percent increase over 1989. Of this number, 566,000 units (50.7%) were transfused, 5,000 (4.4%) transferred to the allogeneic supply, and 546,000 (48.9%) discarded. Of 436,000 directed‐donation units, 136,000 (31.2%) were transfused, 57,000 (13.1%) transferred to allogeneic supply, and 243,000 (55.7%) discarded. The total allogeneic blood supply, including imports, decreased by 7.4 percent from 1989, and allogeneic blood transfusions, including those to children, decreased by 8.6 percent. Over 8,300,000 platelet units were transfused; of these, some 3,600,000 were apheresis platelets. In addition, 2,255,000 units of plasma and 939,000 units of cryoprecipitate were transfused.CONCLUSION: While the US blood supply was adequate for transfusion needs in 1992, blood collections and red cell transfusions had decreased substantially since 1989.
Increased detection of hepatitis C virus infection in commercial plasma donors by a third‐generation screening assay
Authors: Lee S.R. , Wood C.L. , Lane M.J. , Francis B. , Gust C. , Higgs C.M. , Nelles M.J. , Polito A. , DiNello R. , Achord D. 
Published: March 2003

BACKGROUND: Routine screening of blood donations with second‐generation hepatitis hepatitis C virus (HCV) assays has substantially reduced the occurrence of posttransfusion hepatitis. However, following the development of third‐generation assays, several studies indicated that these assays may identify HCV‐infected individuals who are not identified by second‐generation assays.STUDY DESIGN AND METHODS: The sensitivity of a third‐generation HCV enzyme‐linked immunosorbent assay (ELISA‐3) was compared with a second‐generation ELISA (ELISA‐2) in a side‐by‐side study of 9936 commercial blood donors. ELISA‐reactive specimens were subjected to supplemental analysis by third‐generation recombinant immunoblot assay and polymerase chain reaction.RESULTS: ELISA‐3 demonstrated greater sensitivity than ELISA‐2, detecting 1 additional recombinant immunoblot assay‐positive specimen per 2000 tested. ELISA‐3 also detected 1 additional HCV‐infectious polymerase chain reaction‐positive unit among approximately 10,000 units screened.CONCLUSION: The incremental sensitivity achieved with ELISA‐3 can be expected to eliminate approximately 20 infectious donations per week among those made by commercial donors in the United States. In accordance with previous studies, most of the improved sensitivity of ELISA‐3 derives from its increased detection of anti‐c33c (NS3), rather than from the inclusion of HCV antigen NS5.
Preparation of white cell‐reduced red cells by filtration: comparison of a bedside filter and two blood bank filter systems
Authors: Sprogøe‐Jakobsen U. , Saetre A. M. , Georgsen J. 
Published: March 2003

BACKGROUND: Concern has been raised about the quality of white cell (WBC)‐reduced red cells (RBCs) obtained by bedside filtration. The bedside performance and workload of a routine bedside filter have been compared to the laboratory performance and workload of two blood bank filter systems.STUDY DESIGN AND METHODS: Buffy coat‐depleted saline‐ adenine‐glucose‐mannitol (SAGM) RBCs (90 units) were prepared. Thirty units were filtered with each of the two blood bank filter systems, and 30 units were filtered (but not transfused) with the bedside filter in a clinical department after 8 to 24 days of storage. The RBCs lost and the postfiltration WBC content (Nageotte chamber) were determined for all filtered units, and the workload associated with filtration by each of the filter systems/filter was assessed. Units with a postfiltration content of > or = 2 × 10(6) WBCs were regarded as filtration failures.RESULTS: Four (13%) of the 30 units filtered at the bedside were filtration failures, compared to no failures with either of the blood bank filter systems. In addition, the median WBC content (0.14 × 10(6)) of the units filtered at the bedside (2 units/filter) was significantly higher than that of the units filtered in the blood bank (0.05 × 10(6)). The RBC loss was significantly higher with the filter systems than with the bedside filter, provided 2 units per filter were processed with the latter. The timed workload of the filter systems was 45 to 75 minutes per 12 units, which was similar to the time required for bedside filtration.CONCLUSION: Bedside filtration of 2 units of stored buffy coat‐depleted SAGM RBCs per filter resulted in a higher incidence of filtration failure and higher postfiltration WBC content than did laboratory filtration of 1 unit of fresh buffy coat‐depleted SAGM RBCs per filter with either of two blood bank filter systems.
Evidence that CDw108 membrane protein bears the JMH blood group antigen
Authors: Mudad R. , Rao N. , Angelisova P. , Horejsi V. , Telen M. J. 
Published: March 2003

BACKGROUND: CDw108 is a cluster‐of‐differentiation antigen that resides on a glycosylphosphatidylinositol (GPI)‐linked protein; it has not previously been shown to be expressed on red cells. JMH is a high‐ frequency red cell blood group antigen that resides on a GPI‐linked protein of molecular weight similar to that bearing CDw108. The purpose of this study was to investigate whether CDw108 is expressed on red cells and whether it resides on the same membrane protein as does JMH.STUDY DESIGN AND METHODS: Murine monoclonal antibodies to CDw108, MEM‐ 121 and MEM‐150, as well as a murine monoclonal antibody and human antibodies to JMH were used in radioimmunoassay, inhibition assay, Western blotting, and monoclonal antibody‐specific immobilization of erythrocyte antigen assay.RESULTS: MEM‐121 and MEM‐150 were found to bind to red cells, and MEM‐150 blocked binding of human anti‐JMH to red cells. Anti‐CDw108 and anti‐JMH identified red cell membrane proteins that were of similar size and that were absent from JMH‐negative red cells on Western blotting. MEM‐150 and MEM‐121 also immobilized the same protein that reacted with human anti‐JMH.CONCLUSION: CDw108 is expressed on red cells and resides on the same GPI‐linked membrane protein as does the JMH blood group antigen.