bluuebunny/crossref_metadata_2025 huggingface dataset:
Variations in Nurse Practitioner Use in Veterans Affairs Primary Care Practices
Authors: Huang Patty Y. , Yano Elizabeth M. , Lee Martin L. , Chang Betty L. , Rubenstein Lisa V.
Published: July 2004

Background. Increasingly, primary care practices include nurse practitioners (NPs) in their staffing mix to contain costs and expand primary care. To achieve these aims in U.S. Department of Veterans Affairs medical centers (VAMCs), national policy endorsed involvement of NPs as primary care (PC) providers.

Objectives. To evaluate the degree to which VAMCs incorporated NPs into PC practices between 1996 and 1999, and to identify the internal and external practice environment features associated with NP use.

Study Design. We surveyed 131 PC directors of all VAMCs in 1996 and 1999 to ascertain the staffing and characteristics of the PC practice and parent organization (e.g., academic affiliation, level of physician staffing, use of managed care arrangements), and drew on previously published studies and HRSA State Health Workforce Profiles to characterize each practice's regional health care environment (e.g., geographic region, state NP practice laws, state managed care penetration). Using multivariate linear regression, we evaluate the contribution of these environmental and organizational factors on the number of NPs/10,000 PC patients in 1999, controlling for the rate of NP use in 1996.

Principal Findings. From 1996–1999, NP use increased from 75 percent to 90 percent in VA PC practices. The mean number of NPs per practice increased by about 60 percent (2.0 versus 3.2; p<.001), while the rate of NPs/10,000 PC patients trended upward (2.2 versus 2.7; p=.09). Staffing of other primary care clinicians (e.g., physicians and physician assistants per practice) remained stable, while the NP‐per‐physician rate increased (0.2 versus 0.4; p<.001). After multivariate adjustment, greater reliance on managed‐care‐oriented provider education programs (p=.02), the presence of NP training programs (p=.05), and more specialty‐trained physicians/10,000 PC patients (p=.09) were associated with greater NP involvement in primary care.

Conclusions. Staffing models in VA PC practices have, in fact, changed, with NPs having a greater presence. However, we found substantial practice‐based variations in their use, suggesting that more research is needed to better understand how they have been integrated into practice and what impact their involvement has had on the VA's ability to achieve its restructuring goals.
Antiretroviral Therapy and Health Care Utilization: A Study of Privately Insured Men and Women with HIV Disease
Authors: Hellinger Fred J. , Encinosa William E.
Published: July 2004

Objective. To compare the use of antiretroviral therapy and other health care resources by women and men with HIV disease who are privately insured.

Data Sources. Data were obtained from the MarketScan Commercial Claims and Encounter Database produced by the Medstat Group, Inc., of Ann Arbor, Michigan. This database includes eligibility files as well as claims data for inpatient care, outpatient care, physician services, and prescription drugs for enrollees in employer‐sponsored benefit plans for 24 large employers around the nation.

Study Design. Examine utilization by 2,026 privately insured persons (1,494 men and 532 women) with HIV disease in calendar year 2000 under the age of 65.

Principal Findings. Using a simple comparison, we found that 71 percent of men (68.7 to 73.3 percent is 95 percent confidence interval) and 39 percent of women (35.1 to 43.5 percent is 95 percent confidence interval) with HIV disease received antiretroviral therapy. We also found that the average annual drug cost was $9,037 for a man ($8,372 to $9,702 is 95 percent confidence interval) and $3,893 for a woman ($3,476 to $4,490 is 95 percent confidence interval). Furthermore, we found that the out‐of‐pocket expenses comprised 10 percent of total expenses for men ($1,617 out of $16,405) and 4 percent for women ($405 out of $10,397).

Conclusion.

There are major differences in the utilization and cost of health care between privately insured men and women with HIV disease.
Economic Profiling of Primary Care Physicians: Consistency among Risk‐Adjusted Measures
Authors: Thomas J. William , Grazier Kyle L. , Ward Kathleen
Published: July 2004

Objective. To investigate whether different risk‐adjustment methodologies and economic profiling or “practice efficiency” metrics produce differences in practice efficiency rankings for a set of primary care physicians (PCPs).

Data Source. Twelve months of claims records (inpatient, outpatient, professional, and pharmacy) for an independent practice association HMO.

Study Design. Patient risk scores obtained with six profiling risk‐adjustment methodologies were used in conjunction with claims cost tabulations to measure practice efficiency of all primary care physicians who managed 25 or more members of an HMO.

Data Collection. For each of the risk‐adjustment methodologies, two measures of “efficiency” were constructed: the standardized cost difference between total observed (standardized actual) and total expected costs for patients managed by each PCP, and the ratio of the PCP's total observed to total expected costs (O/E ratio). Primary care physicians were ranked from most to least efficient according to each risk‐adjusted measure, and level of agreement among measures was tested using weighted kappa. Separate rankings were constructed for pediatricians and for other primary care physicians.

Findings. Moderate to high levels of agreement were observed among the six risk‐adjusted measures of practice efficiency. Agreement was greater among pediatrician rankings than among adult primary care physician rankings, and, with the standardized difference measure, greater for identifying the least efficient than the most efficient physicians. The O/E ratio was shown to be a biased measure of physician practice efficiency, disproportionately targeting smaller sized panels as outliers.

Conclusions. Although we observed moderate consistency among different risk‐adjusted PCP rankings, consistency of measures does not prove that practice efficiency rankings are valid, and health plans should be careful in how they use practice efficiency information. Indicators of practice efficiency should be based on the standardized cost difference, which controls for number of patients in a panel, instead of O/E ratio, which does not.
Coding Response to a Case‐Mix Measurement System Based on Multiple Diagnoses
Authors: Preyra Colin
Published: July 2004

Objective. To examine the hospital coding response to a payment model using a case‐mix measurement system based on multiple diagnoses and the resulting impact on a hospital cost model.

Data Sources. Financial, clinical, and supplementary data for all Ontario short stay hospitals from years 1997 to 2002.

Study Design. Disaggregated trends in hospital case‐mix growth are examined for five years following the adoption of an inpatient classification system making extensive use of combinations of secondary diagnoses. Hospital case mix is decomposed into base and complexity components. The longitudinal effects of coding variation on a standard hospital payment model are examined in terms of payment accuracy and impact on adjustment factors.

Principal Findings. Introduction of the refined case‐mix system provided incentives for hospitals to increase reporting of secondary diagnoses and resulted in growth in highest complexity cases that were not matched by increased resource use over time. Despite a pronounced coding response on the part of hospitals, the increase in measured complexity and case mix did not reduce the unexplained variation in hospital unit cost nor did it reduce the reliance on the teaching adjustment factor, a potential proxy for case mix. The main implication was changes in the size and distribution of predicted hospital operating costs.

Conclusions. Jurisdictions introducing extensive refinements to standard diagnostic related group (DRG)‐type payment systems should consider the effects of induced changes to hospital coding practices. Assessing model performance should include analysis of the robustness of classification systems to hospital‐level variation in coding practices. Unanticipated coding effects imply that case‐mix models hypothesized to perform well ex ante may not meet expectations ex post.
Consumer Experiences in a Consumer‐Driven Health Plan
Authors: Christianson Jon B. , Parente Stephen T. , Feldman Roger
Published: July 2004

Objective. To assess the experience of enrollees in a consumer‐driven health plan (CDHP).

Data Sources/Study Setting. Survey of University of Minnesota employees regarding their 2002 health benefits.

Study Design. Comparison of regression‐adjusted mean values for CDHP and other plan enrollees: customer service, plan paperwork, overall satisfaction, and plan switching. For CDHP enrollees only, use of plan features, willingness to recommend the plan to others, and reports of particularly negative or positive experiences.

Principal Findings. There were significant differences in experiences of CDHP enrollees versus enrollees in other plans with customer service and paperwork, but similar levels of satisfaction (on a 10‐point scale) with health plans. Eight percent of CDHP enrollees left their plan after one year, compared to 5 percent of enrollees leaving other plans. A minority of CDHP enrollees used online plan features, but enrollees generally were satisfied with the amount and quality of the information provided by the CDHP. Almost half reported a particularly positive experience, compared to a quarter reporting a particularly negative experience. Thirty percent said they would recommend the plan to others, while an additional 57 percent said they would recommend it depending on the situation.

Conclusions. Much more work is needed to determine how consumer experience varies with the number and type of plan options available, the design of the CDHP, and the length of time in the CDHP. Research also is needed on the factors that affect consumer decisions to leave CDHPs.
Early Experience with Employee Choice of Consumer‐Directed Health Plans and Satisfaction with Enrollment
Authors: Fowles Jinnet Briggs , Kind Elizabeth A. , Braun Barbara L. , Bertko John
Published: July 2004

Objective. To assess the initial impact of offering consumer‐defined health plan (CDHP) options on employees.

Data Sources/Study Setting. A mail survey of 4,680 employees in the corporate offices of Humana Inc. in June 2001.

Study Design. The study was a cross‐sectional mail survey of employees aged 18 and older who were eligible for health care benefits. The survey was conducted following open enrollment. The primary outcome is the choice of consumer‐directed health plan or not; the secondary outcome is satisfaction with the enrollment process. Important covariates include sociodemographic characteristics (age, gender, race, educational level, exempt or nonexempt status, type of coverage), health status, health care utilization, and plan design preferences.

Data Collection Methods. A six‐page questionnaire was mailed to the home of each employee, followed by a reminder postcard and two subsequent mailings to nonrespondents.

Principal Findings. The response rate was 66.2 percent. Seven percent selected one of the two new plan options. Because there were no meaningful differences between employees choosing either of the two new options, these groups were combined in multivariate analysis. A logistic regression modeled the likelihood of choosing the novel plan options. Those selecting the new plans were less likely to be black (odds ratio [OR] 0.46), less likely to have only Humana coverage (OR 0.30), and more likely to have single coverage (OR 1.77). They were less likely to have a chronic health problem (OR 0.56) and more likely to have had no recent medical visits (OR 3.21). They were more likely to believe that lowest premiums were the most important plan attribute (OR 2.89) and to think there were big differences in the premiums of available plans (OR 5.19). Employees in fair or poor health were more likely to have a difficult time during the online enrollment process. They were more likely to find the communications very helpful (OR 0.42) and the benefits information very understandable (OR 0.38). They were less likely to feel that they had enough time to make their enrollment decision (OR 0.47).

Conclusions. Employees who were attracted to the new CDHP plan options valued the attributes that distinguished these plans from other choices. The shift to consumer‐defined plans and to the electronic provision of information, however, requires a significant increase in the communication support for all employees, but particularly for those in fair or poor health whose information needs are the most complex and individualized.
Iron storage indices and risk of bacterial infections in hemodialysis patients
Authors: Teehan Geoffrey S , Ruthazer Robin , Balakrishnan Vaidyanathapuram S , Snydman David , Jaber Bertrand L
Published: July 2004

Background:  Infection is the second leading cause of death among hemodialysis (HD) patients. Because iron overload may be a risk factor for bacterial infection, concerns about excessive use of intravenous (IV) iron have arisen. In this retrospective analysis, we explored the relationship between target iron storage indices, as outlined in the Dialysis Outcomes Quality Initiative (DOQI) guidelines, and the incidence of bacterial infections.

Methods:  We reviewed the charts of 87 HD patients who received their first course of IV iron at our dialysis unit between 1997 and 2001. Transferrin saturation (TSAT) rate, ferritin level, and other clinical/laboratory measures were recorded at baseline. Patients were followed for up to 2 years for the outcomes of bacteremia and bacterial pneumonia and censored at death, end‐of‐study observation, or kidney transplantation. Cox proportional hazards regression was used to evaluate the relationship of bacterial infections to iron storage indices.

Results:  Thirty‐two patients had at least one episode of bacterial infections. In multivariate analyses, after adjusting for sex and venous catheter use, iron‐replete state (ferritin > 100 ng/mL and TSAT > 20%) was associated with a threefold higher risk of bacterial infections (95% CI 1.3–6.6; p = 0.01). Although diabetes mellitus and lower serum albumin had a nonsignificant trend toward an increased risk of bacterial infections, no such relationship was seen with the first 3‐month cumulative IV iron dose.

Conclusions:  This study suggests an increased risk for bacterial infections at modest levels of iron stores (ferritin > 100 ng/mL and TSAT > 20%) among HD patients initiating IV iron. Large prospective studies are needed to confirm these relationships.
Heparin‐induced thrombocytopenia during renal replacement therapy
Authors: Davenport Andrew
Published: July 2004

There is increasing awareness that antibodies to heparin/platelet factor 4 complex can develop in both those with acute renal failure treated with continuous forms of renal replacement therapy and, to a lesser extent, regular hemodialysis patients. Clinical manifestations include premature clotting of the extracorporeal circuit and increased central venous thrombosis with indwelling venous dialysis catheters, associated with thrombocytopenia and increased platelet activation. Nevertheless, a minority of patients who develop heparin/platelet factor 4 antibodies do not have thrombocytopenia or thrombosis. When systemic anticoagulation is also required to treat venous thrombosis, then synthetic heparinoids or the direct thrombin inhibitors argatroban or recombinant hirudins are the agents of choice. Neither the synthetic heparinoids nor hirudin, however, are without their own problems, in that a minority of patients may have cross‐reacting antibodies against the currently available heparinoids, and antibodies may similarly develop against recombinant hirudin, in this case leading to a potentiation of anticoagulant activity and increased risk of hemorrhage.
Vestigial prototroch in a basal nemertean,Carinoma tremaphoros(Nemertea; Palaeonemertea)
Authors: Maslakova S. A. , Martindale M. Q. , Norenburg J. L.
Published: July 2004

SummaryNemerteans have been alleged to belong to a protostome clade called the Trochozoa that includes mollusks, annelids, sipunculids, echiurids, and kamptozoans and is characterized by, among other things, the trochophore larva. The trochophore possesses a prototroch, a preoral belt of specialized ciliary cells, derived from the trochoblast cells. Nemertea is the only trochozoan phylum for which presence of the trochophore larva possessing a prototroch had never been shown. However, so little is known about nemertean larval development that comparing it with development of other trochozoans is difficult. Development in the nemertean clade Pilidiophora is via a highly specialized planktonic larva, the pilidium, and most of the larval body is lost during a drastic metamorphosis. Other nemerteans (hoplonemerteans and palaeonemerteans) lack a pilidium, and their development is direct, forming either an encapsulated or planktonic “planuliform” larva, producing a juvenile without a dramatic change in body plan. We show that early in the development of a member of a basal nemertean assemblage, the palaeonemerteanCarinoma tremaphoros, large squamous cells cover the entire larval surface except for the apical and posterior regions. Although apical and posterior cells continue to divide, the large surface cells cleavage arrest and form a contorted preoral belt. Based on its position, cell lineage, and fate, we suggest that this belt corresponds to the prototroch of other trochozoans. Lack of differential ciliation obscures the presence of the prototroch inCarinoma, but differentiation of the trochoblasts is clearly manifested in their permanent cleavage arrest and ultimate degenerative fate. Our results allow a meaningful comparison between the development of nemerteans and other trochozoans. We review previous hypotheses of the evolution of nemertean development and suggest that a trochophore‐like larva is plesiomorphic for nemerteans while a pilidium type of development with drastic metamorphosis is derived.
Twenty ways to lose your bladder: common natural mutants in zebrafish and widespread convergence of swim bladder loss among teleost fishes
Authors: McCune Amy R. , Carlson Rose L.
Published: July 2004

SummaryConvergence is an important evolutionary phenomenon often attributed solely to natural selection acting in similar environments. The frequency of mutation and number of ways a phenotypic trait can be generated genetically, however, may also affect the probability of convergence. Here we report both a high frequency of loss of gas bladder (swim bladder) mutations in zebrafish and widespread convergent loss of gas bladders among teleost fishes. The phenotypes of 22 of 27 recessive lethal mutations, carried by a sample of 26 wild‐caught zebrafish, involve loss or noninflation of the gas bladder. Nine of these bladderless mutations showed no other obvious phenotypic abnormalities other than the lack of an inflated gas bladder. At least 19 of the 22 bladderless mutations are genetically distinct, as shown by unique morphology or complementation. Although we were not able to obtain eggs for all 21 required crosses to demonstrate definitively that the remaining three mutations are different from all other bladderless mutations, all available evidence suggests that these mutants are also distinct. At least 79 of 425 families of extant teleosts include one or more species lacking a gas bladder as adults. Analysis of the trait's phylogenetic distribution shows that the gas bladder has been lost at least 30–32 times independently. Although adaptive explanations for gas bladder loss are convincing, a developmental bias toward bladderless phenotypes may also have contributed to the widespread convergence of this trait among teleosts. If gas bladder development in teleosts is as vulnerable to genetic perturbation as it is in zebrafish, then perhaps a supply of bladderless phenotypes has been readily available to natural selection under conditions for which it is advantageous not to have a gas bladder. In this way, developmental bias and selection can work together to produce widespread convergence.
Measuring changes in articulate brachiopod morphology before and after the Permian mass extinction event: do developmental constraints limit morphological innovation?
Authors: Ciampaglio Charles N.
Published: July 2004

SummaryThe pattern of decreasing disparity has been observed in both the metazoans and metaphytes throughout the Phanerozoic. The pattern is manifest as a decreasing trend in the origination of higher taxa. Currently, two competing evolutionary hypotheses have been proposed to explain this phenomenon: the empty ecospace hypothesis and the developmental constraint hypothesis. To empirically distinguish between these hypotheses, the change in disparity before and after the end‐Permian mass extinction event was measured in the articulated brachiopods. The assumption is that ecospace‐limiting constraints are removed after mass extinctions revealing the effect of developmental constraints. For each taxon within the group, both continuous and discrete character sets were analyzed. Four different measures of disparity were used to analyze each character suite. Additionally, a separate analysis was performed on a subset of the articulated brachiopods, the rhynchonellids and terebratulids. In most cases investigated, disparity rebounded to comparable levels, with the rhynchonellids and terebratulids showing the largest increase in disparity after the end‐Permian extinction, a clear example of an increase in disparity without a significant increase in taxonomic diversity. The results indicate that developmental constraints may not be responsible for the decreasing disparity in this group. The more likely scenario is that increasingly structured ecological guilds have made it much more difficult for large increases in disparity to occur.
The effect of development on the direction of evolution: toward a twenty‐first century consensus
Authors: Arthur Wallace
Published: July 2004

SummaryOne of the most important questions in evolutionary biology is: what orients the evolutionary process? That is, what causes evolution to proceed toward certain developmental trajectories, and hence phenotypes, rather than others? In particular, there has been prolonged controversy over whether the direction of evolution is determined solely by external factors or whether the nature of the ontogenetic process, and the ways in which it can be altered by mutations in developmental genes, may also play a major role. Here, I examine this issue, concentrating on the following: the possible evolutionary orienting role of “developmental bias;” the question of whether selection can and/or will break bias; the extent to which bias is already incorporated in quantitative genetic studies; and ways of approaching the possible role of bias in the origin of evolutionary novelties. Finally, I suggest that developmental bias may provide a focal point for the coming together of conceptual and practical approaches to evo‐devo.
Recognition of cytomegalovirus clinical isolate antigens by sera from cytomegalovirus‐negative blood donors
Authors: Rahbar A.R. , Sundqvist V.‐A.S. , Wirgart B. Zweygberg , Grillner L. , Söderberg‐Naucler C.
Published: July 2004

BACKGROUND:  The most common way to prevent transmission of CMV by blood transfusion is to use blood products from seronegative donors. Screening of blood donors for CMV infection is usually based on detection of antigens obtained from the CMV laboratory strain AD 169. Recent evidence suggests that approximately up to 20 percent of CMV‐negative blood donors may in fact be CMV‐DNA positive by PCR analyses.

STUDY DESIGN AND METHODS:  In this study, sera from CMV‐seronegative, CMV‐seropositive, and CMV‐DNA‐positive/seronegative individuals, and from patients with acute and convalescent CMV infection for detection of CMV antibodies were analyzed. CMV antigens pre‐pared from cells infected with CMV clinical isolates or the CMV laboratory strain AD 169 in ELISA and Western blot assays were used.

RESULTS:  All CMV‐positive sera from blood donors were seropositive for the CMV antigens prepared from AD 169 (A2) or from a CMV clinical isolate (C6). Interestingly, whereas all CMV‐negative blood donors were negative in tests for the CMV antigen A2, 36 percent were CMV seropositive using the CMV antigen C6 in ELISA.

CONCLUSION:  The data suggest that a substantial number of CMV‐seronegative/CMV‐DNA‐positive serum samples contain antibodies that recognize CMV clinical isolate antigens.
Fully automated processing of buffy‐coat–derived pooled platelet concentrates
Authors: Janetzko Karin , Klüter Harald , Waeg Geert van , Eichler Hermann
Published: July 2004

BACKGROUND:  The OrbiSac device, which was develo‐ped to automate the manufacture of buffy‐coat PLT con‐centrates (BC‐PCs), was evaluated.

STUDY DESIGN AND METHODS:  In‐vitro characteristics of BC‐PC preparations using the OrbiSac device were compared with manually prepared BC‐PCs. For standard processing (Std‐PC, n = 20), four BC‐PCs were pooled using 300 mL of PLT AS (PAS) followed by soft‐spin centrifugation and WBC filtration. The OrbiSac pre‐paration (OS‐PC, n = 20) was performed by automated pooling of four BC‐PCs with 300 mL PAS followed by centrifugation and inline WBC filtration. All PCs were stored at 22°C. Samples were withdrawn on Day 1, 5, and 7 evaluating PTL count, blood gas analysis, glucose, lactate, LDH, β‐thromboglobulin, hypotonic shock response, and CD62p expression.

RESULTS:  A PLT content of 3.1 ± 0.4 × 1011 (OS‐PCs) versus 2.7 ± 0.5 × 1011 (Std‐PCs, p < 0.05) was found. A CV of 19 percent (Std‐PC) versus 14 percent (OS‐PC) suggests more standardization in the OS group. At Day 7, the Std‐PCs versus OS‐PCs showed a glucose consumption of 1.03 ± 0.32 µmol per 109 PLT versus 0.75 ± 0.25 µmol per 109 PLT (p < 0.001), and a lactate production of 1.50 ± 0.86 µmol per 109 versus 1.11 ± 0.61 µmol per 109 (p < 0.001). The pH (7.00 ± 0.19 vs. 7.23 ± 0.06; p < 0.001), pO2 (45.3 ± 18 vs. 31.3 ± 10.4 mmHg; p < 0.01), and HCO3 levels (4.91 ± 1.49 vs. 7.14 ± 0.95 mmol/L; p < 0.001) suggest a slightly better aerobic metabolism within the OS group. Only small differences in CD62p expression was observed (37.3 ± 12.9% Std‐PC vs. 44.8 ± 6.6% OS‐PC; p < 0.05).

CONCLUSION:  The OrbiSac device allows an improved PLT yield without affecting PLT in‐vitro characteristics and may enable an improved consistency in product volume and yield.
Hepatitis C core antigen in Polish blood donors
Authors: Letowska Magdalena , Brojer Ewa , Mikulska Maria , Gronowska Agnieszka , Rosiek Aleksandra
Published: July 2004

BACKGROUND:  The goal of this study was to evaluate the feasibility of adopting the HCV core antigen ELISA (HCVcAg) for routine screening of Polish blood donors.

STUDY DESIGN AND METHODS:  A total of 133,279 donor samples were tested by ORTHO HCVcAg. All repeatedly reactive (RR) samples were tested by neutrali‐zation test for confirmation, RIBA HCV for anti‐HCV, and by Cobas Amplicore for HCV RNA. All donations were tested for ALT level.

RESULTS:  The HCVcAg test specificity was 99.94 percent. In total, 1499 donations (1.12%) were initially reactive and 124 (0.09%) were RR. Antibodies to HCV were found in 22 out of 124 donors and HCV RNA was detected in 19 out of 22. In 10 out of the 19 HCV‐RNA‐positive donors, the HCVcAg neutralization test was positive. Among the 102 HCVcAg RR/anti‐HCV‐negative donors, there were 6 neutralization‐test‐positive indivi‐duals, and all were HCV RNA positive. Elevated ALT level was observed in one of them. During the follow‐up studies of three HCVcAg RR/HCV‐RNA‐positive donors, sero‐convertion was observed 5 to 7 weeks after the initial HCVcAg‐positive result. In all, HCVcAg results became negative once antibodies to HCV were detected.

CONCLUSION:  The HCVcAg test proved to be feasible for routine screening in the Polish Blood Transfusion Service. Six HCVcAg RR/anti‐HCV‐negative donors were identified. The calculated residual risk in this study of donors in the preseroconversion window was 45 per million. Mandatory testing of every blood and plasma donation for HCVcAg or HCV RNA was recommended as of January 2, 2002.
The use of autologous platelet gel to treat difficult‐to‐heal wounds: a pilot study
Authors: Mazzucco Laura , Medici Dante , Serra Massimo , Panizza Renzo , Rivara Giorgio , Orecchia Sara , Libener Roberta , Cattana Elena , Levis Alessandro , Betta Pier Giacomo , Borzini Piero
Published: July 2004

BACKGROUND:  Chronic ulcers can benefit from topical treatment with growth factors (GFs). PLT gel provides tissue regeneration‐inducing GFs. The aim of this study was to verify the effectiveness of autologous PLT gel in the treatment of nonhealing skin lesions.

STUDY DESIGN AND METHODS:  PLT gel was pro‐duced by treating PLTs with autologous thrombin. Two groups of patients were investigated: patients with dehis‐cent sternal wounds and patients with necrotic skin ulcers. Patients treated with PLT gel were retrospectively compared with patients having similar lesions but undergoing conventional treatment. The clinical endpoints of the study were the healing rate, the length of hospital stay, and/or the time required to bring about adequate tissue regeneration in order to undergo reconstructive plastic surgery.

RESULTS:  In patients with treated dehiscent sternal wounds the healing rate (3.5 vs. 6.0 wks, p = 0.0002) and hospital stay (31.5 vs. 52.5 days, p < 0.0001) were signi‐ficantly reduced. Patients with treated necrotic skin ulcers required a notably shorter time to have surgery (median 15.0 vs. 35.5 wks, p < 0.0001). Neither adverse reactions nor in‐situ recurrences were observed.

CONCLUSIONS:  Patients with chronic unhealing wounds showed substantial improvement when treated with PLT gel lesion dressings.
Posttransfusion recovery of stored red blood cells in very low birth weight infants using a hemoglobin balance model
Authors: Bechensteen Anne Grete , Chapel Sunny , Veng‐Pedersen Peter , Widness John A.
Published: July 2004

BACKGROUND:  A Hb balance model was used in very low birth weight (VLBW) infants to predict posttransfusion Hb levels from which we inferred allogeneic RBC recovery after transfusion of RBCs stored for varying periods of time.

STUDY DESIGN AND METHODS:  Premature VLBW infants receiving RBC transfusions during the 1st month of life were evaluated retrospectively for RBC survival of stored donor blood. Actual Hb levels measured in infant blood 1 and 2 days after RBC transfusions were com‐pared to those predicted using a Hb balance model based on factors affecting blood Hb loss and gain. Transfusions were subgrouped according to whether or not infants were clinically stable at the time of RBC transfusion. Model‐predicted RBC recovery was also evaluated relative to duration of RBC storage.

RESULTS:  Model‐predicted mean (± SD) Hb levels 2 days after transfusion among the 30 VLBW infants receiv‐ing a total of 57 RBC transfusions were only 4 percent higher than actual values observed (15.2 ± 1.2 g/dL vs. 14.7 ± 1.4, respectively; p < 0.05). The infant's clinical status at the time of transfusion did not affect predicted 1‐ and 2‐day posttransfusion RBC recovery. Model‐predicted recovery of transfused RBCs was modestly, but significantly, decreased with increasing duration of donor RBC storage (i.e., 10% lower by 42 days—the maximal allowed storage period for donor blood [p < 0.01]).

CONCLUSIONS:  Our model‐predicted RBC survival results are consistent with—but not direct evidence of—hemolysis of donor blood after RBC transfusion. Although observed post‐RBC Hb levels 2 days after transfusion averaged only 4 percent less than predicted, model‐predicted survival of donor RBCs at 42 days suggested a modest decrease (i.e., by 10%).
Long‐term survival after blood transfusion: a population based study in the North of England
Authors: Wallis Jonathan P. , Wells Angus W. , Matthews John N. , Chapman Catherine E.
Published: July 2004

BACKGROUND:  Blood transfusion may transmit infec‐tious diseases with long incubation periods. Estimation of the risks of transmission of such disease requires know‐ledge of long‐term survival of transfused patients. No such information is available in the UK, where there is particular concern about possible transmission by trans‐fusion of variant CJD.

STUDY DESIGN AND METHODS:  Information on survival after transfusion and demographics was collected for all patients transfused during June 1994 in a popula‐tion of 2.9 million served by a single blood center.

RESULTS:  A total of 2899 patients were transfused with 10,760 units of RBCs (99% of RBCs issued during the study period). Follow‐up to death or 5 years was com‐pleted for 98.2 percent, and 46.9 percent of all transfusion recipients were alive at 5 years; 41 percent of transfused RBC units and 36 percent of transfused FFP were given to patients who were alive at 5 years. Median age at transfusion was 67 years (mean, 60.9 years). Shorter patient survival was associated with increasing patient age, increasing numbers of RBC units transfused, trans‐fusion of plasma or PLTs, and nonsurgical indications for transfusion.

CONCLUSIONS:  Posttransfusion survival is lower than estimated in previous decades in other countries. This is probably due to a relative increase in use of transfusion for older patients and for medical indications. Our figures may be used to predict and stratify the risk of infections, such as variant CJD, amongst different groups of transfusion recipients.
Neonatal neutropenia and bacterial sepsis associated with placental transfer of maternal neutrophil‐specific autoantibodies
Authors: Davoren Anne , Saving Kay , McFarland Janice G. , Aster Richard H. , Curtis Brian R.
Published: July 2004

BACKGROUND:  Passively acquired neonatal neutro‐penia is an infrequently reported complication of maternal autoimmune neutropenia (AIN). Two affected siblings are described. The firstborn developed Citrobacter meningitis and was permanently disabled. The second was success‐fully managed with pre‐ and postnatal injections of recom‐binant human granulocyte colony‐stimulating factor (rHuG–CSF).

STUDY DESIGN AND METHODS:  Neutrophil‐specific antibodies were evaluated by flow cytometry (FC), monoclonal antibody immobilization of granulocyte antigens, and granulocyte agglutination assays.

RESULTS:  A neutrophil‐reactive antibody was detected by FC in samples of the mother's serum spanning a 4‐year time frame. This antibody reacted with neutrophils from the mother, father, and their first infant and with 18 of 20 target neutrophils tested. In serologic studies, it was shown that the antibody was not specific for the commonly recognized neutrophil‐specific alloantigens HNA‐1a (NA1), HNA‐1b (NA2), HNA‐1c (SH), HNA‐2a (NB1), or HNA‐3a (5b).

CONCLUSION:  Severe neonatal neutropenia in the two siblings appears to have been caused by placental transfer of a maternal neutrophil‐reactive autoantibody of undetermined specificity. Neutrophil counts should be evaluated in infants born to mothers with chronic neutropenia of possible autoimmune origin so that neutropenic infants can be carefully monitored and antibiotics and/or rHuG–CSF administered if indicated.
The in vitro quality of red blood cells frozen with 40 percent (wt/vol) glycerol at −80°C for 14 years, deglycerolized with the Haemonetics ACP 215, and stored at 4°C in additive solution‐1 or additive solution‐3 for up to 3 weeks
Authors: Valeri C. Robert , Srey Rithy , Tilahun Daniel , Ragno Gina
Published: July 2004

BACKGROUND:  Red blood cells (RBCs) frozen with 40 percent (wt/vol) glycerol, stored at −80°C (mean temperature; range, −65 to −90°C) for 14 years, deglycerolized in the Haemonetics automated cell processor (ACP) 215 with the 325‐mL disposable bowl, and stored at 4°C in additive solution (AS)‐1 or AS‐3 for 21 days were evaluated.

STUDY DESIGN AND METHODS:  A total of 106 units of citrate phosphate dextrose adenine‐1 RBCs were frozen with 40 percent (wt/vol) glycerol in the original 800‐mL polyvinylchloride plastic bag and stored in corrugated cardboard boxes at −80°C for 14 years. The thawed units were deglycerolized with the ACP 215 with a 325‐mL disposable bowl and stored in AS‐1 or AS‐3 at 4°C for 21 days.

RESULTS:  The freeze‐thaw recovery value was 94 ± 4 percent (mean ± SD), the freeze‐thaw‐wash recovery value was 80 ± 7 percent, and there was no breakage. Thirty‐eight units were processed as 19 pairs. Two units of ABO‐matched units were thawed, pooled, divided equally into two units, and deglycerolized. One unit was stored in AS‐1 and the other in AS‐3 at 4°C for 21 days. Units stored in AS‐1 exhibited significantly greater hemolysis than those stored in AS‐3.

CONCLUSIONS:  Acceptable results were achieved when RBCs frozen at −80°C for 14 years were deglycerolized in the ACP 215. Deglycerolized RBCs in AS‐1 exhibited significantly higher hemolysis than those in AS‐3 after storage at 4°C for 7 to 21 days.
Investigation of red blood cells from α1,3‐galactosyltransferase‐knockout pigs for human blood transfusion
Authors: Rouhani Foad J. , Dor Frank J.M.F. , Cooper David K.C.
Published: July 2004

BACKGROUND:  Pigs are a potential source of red blood cells (RBCs) for transfusion into humans, but the pre‐sence of galactose‐α1,3‐galactose (Gal) epitopes on their surface, against which humans have anti‐Gal, has been perceived as a major barrier. α1,3‐Galactosyltransferase gene‐knockout pigs, which do not express Gal epitopes on RBCs (Gal–/–), have recently become available.

STUDY DESIGN AND METHODS:  In vitro, RBCs from Gal–/– pigs were exposed to sera from naïve humans or baboons or from baboons previously sensitized to pig antigens; immunoglobulin binding was measured by flow cytometry, and cytotoxicity, by a hemolytic assay. In vivo, relatively small numbers of Gal–/– RBCs were transfused into two nonsensitized untreated baboons. The survival of pig RBCs was detected by flow cytometry.

RESULTS:  In vitro, binding of immunoglobulin (Ig) M from naïve human or baboon sera was detected to Gal–/– RBCs but was significantly less than to Gal+/+ RBCs; IgG binding to Gal–/– RBCs was absent or minimal. Sera had minimal cytotoxicity to Gal–/– RBCs compared to Gal+/+ RBCs. Sensitized baboon sera demonstrated much higher IgG binding to Gal–/– RBCs and increased cytotoxicity, but again these were less than to Gal+/+ RBCs. In vivo, the transfusion of relatively small volumes of Gal–/– RBCs was followed by detection of the cells in the baboon's blood for only 5 minutes.

CONCLUSION:  Pig RBCs are rapidly phagocytosed from the primate circulation by a mechanism not involving anti‐Gal.
White particulate matter: report of the ad hoc industry review group
Authors: McCullough Jeffrey , Dodd Roger , Gilcher Ron , Murphy Scott , Sayers Merlyn
Published: July 2004

BACKGROUND:  In January 2003, blood center person‐nel in the American Red Cross, Southern Region in Atlanta, noticed whitish particulate material (WPM) that had not been observed previously in several units of red blood cells (RBCs). An expert panel was formed to evaluate studies of the material and make appropriate recommendations

STUDY DESIGN AND METHODS:  The expert panel reviewed information provided by several investigations and organizations. This included: background informa‐tion, and experiences relating to WPM; WPM composi‐tion; factors promoting WPM formation; risk of WPM (if any) to patients; and recommendations to prevent future occurrences.

RESULTS:  WPM is derived from blood. No data suggest that external contamination or collection set components contribute to WPM development. A major constituent of WPM is platelets (PLTs). WPM is most commonly observed in RBCs that have been subjected to a hard spin without PLT separation. WPM is rarely, if ever, observed in RBCs that have been subjected to leukoreduction.

CONCLUSIONS:  (1) WPM is not new, can be prevented, and can be removed. (2) WPM contains PLTs, white blood cells, fibrin, and cellular debris. (3) Changes in blood handling are not necessary. (4) WPM may be more frequent when higher g forces are used in component preparation. (5) Enhanced visual inspection of blood components need not be continued. (6) It appears that WPM may not form in RBC collected using automated devices. (7) WPM did not pose a risk to patients but should be avoided.
Investigation of Poor Academic Achievement in Children with Duchenne Muscular Dystrophy
Authors: Hinton V. J. , De Vivo D. C. , Fee R. , Goldstein E. , Stern Y.
Published: July 2004

Duchenne Muscular Dystrophy (DMD) is a neurogenetic developmental disorder that presents with progressive muscular weakness. It is caused by a mutation in a gene that results in the absence of specific products that normally localize to muscle cells and the central nervous system (CNS). The majority of affected individuals have IQs within the normal range, generally with lower verbal than performance IQ scores. Prior work has demonstrated selective deficits on tests of verbal span and immediate memory. For the current study, 26 boys with DMD (and normal intellectual function) and their unaffected siblings were evaluated. Paired comparisons demonstrated that the children with DMD had significantly poorer academic achievement scores than their siblings, even though their vocabulary levels and home and educational environments were comparable. Children with DMD also had more behavioral concerns, physical disabilities, and poorer verbal memory spans. Linear regression indicated that behavioral concerns, executive function, and physical disability did not contribute substantially to academic performance, whereas performance on verbal span did. DMD presents with a selective developmental aberration in verbal span that has wide‐ranging consequences on learning skills.
Neurobehavioral and Psychosocial Issues in Klinefelter Syndrome
Authors: Geschwind Daniel H. , Dykens Elisabeth
Published: July 2004

Klinefelter Syndrome (KS) is a relatively common (1/500 to 1/1,000) genetic syndrome caused by an extra X chromosome in males, leading to an XXY karyotype. In most cases, the physical and neurobehavioral characteristics of KS are relatively mild, and KS is not usually associated with moderate or severe mental retardation. However, KS is often associated with significant language‐based learning disabilities and executive dysfunction, making it a plausible genetic model for understanding the neurobiology of these areas of cognition that are so fundamental to learning in a classroom. Additionally, the psychosocial aspects of KS, which can have a significant impact on school performance and learning, have been explored only on an anecdotal level. We have conducted pilot studies in a small group of KS adolescents and adults to begin to identify the social, emotional, and adaptive behavior issues facing KS subjects and have identified several areas for further research. This includes characterization of mild maladaptive behaviors, as well as significant strengths in other areas. Further work is needed to determine how the social‐emotional and cognitive features of the disorder interact or change over the lifetime of subjects and how the learning disabilities respond to hormonal or cognitive‐based therapy.
Exploring the Relationship Between Text‐Leveling Systems and Reading Accuracy and Fluency in Second‐Grade Students Who Are Average and Poor Decoders
Authors: Compton Donald L. , Appleton Amanda C. , Hosp Michelle K.
Published: July 2004

The purpose of this study was to investigate the relationship between different text‐leveling systems and reading accuracy and fluency in second‐grade students with and without decoding difficulties. Two‐hundred‐forty‐eight second‐grade students, 44 identified as low achieving (LA) and 204 identified as average achieving (AA) in decoding skill, participated in the 15‐week study. During the study teachers collected data weekly on students' text‐reading accuracy and fluency using curriculum‐based measurement (CBM) techniques. Text attributes such as readability, decodability, percentage of high frequency words, average words per sentence, and percentage of multisyllabic words were estimated for each passage. Results using the entire sample of children indicated that accuracy of text reading was uniquely predicted by the percentage of high frequency words in the passages, whereas both the percentage of high frequency words and passage decodability made unique contributions to variance in passage‐reading fluency. Moreover, results suggested that the relationship between text‐leveling variables and reading performance was similar in the LA and AA groups, with only a slight trend favoring a stronger relationship between passage decodability and measures of text‐reading performance in the AA group compared to the LA group.
Relationship between knowledge and attitudes regarding HIV/AIDS among dental school employees and students
Authors: Börsum K. M. , Gjermo P. E.
Published: July 2004

Objectives:  Employees and students at the Faculty of Dentistry, University of Oslo responded to a comprehensive questionnaire regarding knowledge and attitudes towards human immunodeficiency virus (HIV). The intention of the present study was to describe possible relationships between the two.

Method:  The questionnaire consisted of 39 closed questions. The response rate was 75% (436/584). The answers were used to construct additive indices for knowledge and attitudes.

Results:  The knowledge index reflected the number of correct answers concerning risk groups and transmission. A factor analysis revealed three dimensions of attitudes (‘legal’, ‘personal risk’, and ‘personal consequences’), which were analysed separately against knowledge. Correlation analyses (Spearman r) of all respondents together (n = 436) revealed a weak, but statistically significant, positive correlation between knowledge and the ‘legal’ and ‘personal risk’ dimension of attitudes (r = 0.16, P < 0.01; r = 0.21, P < 0.001). The ‘personal consequence’ dimension was not significantly correlated with knowledge (r = 0.06, P > 0.05). The strongest correlation was found between knowledge and the ‘legal’ dimension (r = 0.43, P < 0.001), and knowledge and the ‘personal risk’ dimension (r = 0.41, P < 0.002) amongst fourth year students. No particular group of employees or students displayed a significant correlation between knowledge and the ‘personal consequence’ dimension of attitudes.

Conclusions:  Three dimensions on attitudes concerning patients with HIV/acquired immune deficiency syndrome were identified amongst the respondents. A weak correlation between knowledge and two of the attitudes might indicate that knowledge plays a role in this respect.