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1.
PLoS One ; 19(4): e0300439, 2024.
Article in English | MEDLINE | ID: mdl-38687733

ABSTRACT

INTRODUCTION: Interpretations of patient-reported outcome measures following knee arthroplasty lack context and typically do not account for costs, risks and benefits compared to an alternative treatment. The primary purpose of our paper is to estimate expectations patients have for pain and function destination outcome, six-months following surgery relative to the outcome expected if knee arthroplasty was not done. Secondary purposes were to determine if statistically significant changes in the smallest worthwhile six-month outcome occurred following an interactive discussion and to assess the construct validity of the expected six-month outcome obtained at baseline. METHODS: This was a secondary analysis of a prospective longitudinal cohort study of 121 patients undergoing knee arthroplasty. Smallest worthwhile effect estimates were determined and expected six-month KOOS Pain and Function, daily activity measures were established during a pre-operative visit. RESULTS: The average six-month expected (the destination of interest) KOOS Pain score was 75 (IQR = 64 to 86) and the average KOOS Function, daily activity score was 74 (IQR = 59 to 86). The smallest worthwhile effect discussion led to significant changes in expected destination scores. For example, KOOS Pain expected outcome changed from 87.7 (9.8) to 75.0 (13.6), a statistically significant reduction in expected outcome (t(119) = 16.942, p < 0.001. CONCLUSION: Six-month expected KOOS outcomes following knee arthroplasty were established and approximate the average six-month outcomes reported in the literature. Validity of these estimates was established. These data can be used to aid shared decision-making discussions regarding patient expectations of knee arthroplasty outcomes during a patient encounter.


Subject(s)
Arthroplasty, Replacement, Knee , Humans , Female , Male , Aged , Middle Aged , Prospective Studies , Longitudinal Studies , Patient Reported Outcome Measures , Pain Measurement , Treatment Outcome , Pain, Postoperative/etiology , Activities of Daily Living , Pain
2.
PLoS One ; 19(3): e0299801, 2024.
Article in English | MEDLINE | ID: mdl-38517923

ABSTRACT

BACKGROUND: In 2021, 43% of drug toxicity deaths in Ontario were reported by public health units serving medium-sized urban and rural communities. Safer supply programs (SSPs) have been primarily established in large urban centres. Given this, the current study is based on an evaluation of a SSP based in a medium-sized urban centre with a large catchment area that includes rural and Indigenous communities. The aim of this research paper is to understand the challenges and successes of the nurse practitioner-led SSP from the perspective of program participants. METHODS: Interpretive description was used to understand the experiences of 14 participants accessing a SSP. Each participant was interviewed using a semi-structured approach, and 13 of the interviewees also completed surveys accessed through Qualtrics. An iterative process using NVivo software was used to code interviews, and a constant comparative data analysis approach was used to refine and categorize codes to themes. FINDINGS: Three overarching themes were the result of this analysis: feeling better, renewed hope, and safety. These three themes capture the experiences of participants in the SSP, including both the challenges and successes they faced. CONCLUSION: The findings and subsequent discussion focus on both the key best practices of the program, and areas for future development and improvement. Despite barriers to services, prescribed SSPs are improving the lives of people who use drugs, and the current outcomes align with reports and evaluations from other SSPs across Canada.


Subject(s)
Catchment Area, Health , Humans , Ontario
3.
Mil Med ; 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38531071

ABSTRACT

INTRODUCTION: Soldiers must be able to perform a multitude of physically demanding tasks as part of their regular duty, but their physical readiness is often degraded due to pain and musculoskeletal injury (MSKI). The presence of pain with movement has been associated with increased MSKI risk in Soldiers. Improved awareness of the prevalence of painful movements in uninjured Soldiers could help inform Army injury mitigation efforts. The purpose of this study was to identify the prevalence of pain with movement in a population of healthy active duty Soldiers. MATERIALS AND METHODS: The Selective Functional Movement Assessment-Top Tier Movements (SFMA-TTM), active range of motion (AROM) of the hips and shoulders, and the elicitation of pain with movement were measured in 268 healthy US Army Soldiers. Descriptive statistics were generated for the number of painful movements for each measure and inferential statistics; independent t-test and one-way independent analysis of variance (ANOVA) were used for analysis of the other measures. RESULTS: Greater than half (59%) of the participants reported pain with at least 1 movement and more than 41% reported pain with 2 or more movements. Soldiers reported a mean of 1.35 painful movements on the SFMA-TTM assessment and a mean of 1.54 painful AROM movements. CONCLUSIONS: Pain with functional movement patterns was common across a sample of uninjured Soldiers. The presence of pain with movement warrants further evaluation as it may impact a Soldier's physical performance, risk for future injury, and overall quality of life.

4.
Int J Drug Policy ; 120: 104157, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37574645

ABSTRACT

BACKGROUND: Canada is experiencing an unprecedented drug toxicity crisis driven by a highly toxic unregulated drug supply contaminated with fentanyl, benzodiazepine, and other drugs. Safer supply pilot programs provide prescribed doses of pharmaceutical alternatives to individuals accessing the unregulated drug supply and have been implemented to prevent overdose and reduce related harms. Given the recent emergence of these pilot programs and the paucity of data on implementation challenges, we sought to document challenges in their initial implementation phase. METHODS: We obtained organizational progress reports from Health Canada, submitted between 2020 and 2022 by 11 pilot programs located in British Columbia, Ontario, and New Brunswick. We analyzed the data using deductive and inductive approaches via thematic analysis. Analyses were informed by the consolidated framework for implementation research. RESULTS: We obtained 45 progress reports from 11 pilot programs. Six centres were based in British Columbia, four in Ontario, and one in New Brunswick. Four overarching themes were identified regarding the challenges faced during the establishment and implementation of pilot programs: i) Organizational features (e.g., physical space constraints, staff shortages); ii) Outer contexts (e.g., limited operational funds and resources, structural inequities to access, public perceptions); iii) Intervention characteristics (e.g., clients' unmet medication needs); and iv) Implementation process (e.g., pandemic-related challenges, overly medicalized and high-barrier safer supply models). CONCLUSIONS: Safer supply pilot programs in Canada face multiple inner and outer implementation challenges. Given the potential role of safer supply programs in addressing the drug toxicity crisis in Canada and the possibility of future scale-up, services should be well-supported during their implementation phases. Refining service provision within safer supply programs based on the feedback and experiences of clients and program administrators is warranted, along with efforts to ensure that appropriate medications are available to meet the clients' needs.

5.
Int J Exerc Sci ; 16(3): 1216-1227, 2023.
Article in English | MEDLINE | ID: mdl-38287970

ABSTRACT

Firefighters work in a dangerous profession with high injury rates. Mobility dysfunction in firefighters may impact performance and contribute to injury. The Functional Movement Screen (FMS) is commonly used to evaluate individuals for mobility dysfunction and compensatory movements. The purpose of this study was to identify if mobility is related to firefighters' occupational task performance. This was a retrospective study assessing 29 career firefighters using FMS and occupational performance task scores. Statistical analyses consisted of a multiple linear regression assessing predictors on occupational task performance, and 21 point-biserial correlations ran to assess the relationship between each individual predictor and occupational task performance. Of the 21 point-biserial correlations, four were found to be significant, indicating a relationship between the FMS and occupational task performance. Inline Lunge L had a negative correlation with occupational task time and was statistically significant (rpb = -0.46, p = 0.012); Inline Lunge R had a negative correlation of moderate strength (rpb = -0.583, p = 0.001), Inline Lunge Combined had a negative correlation of moderate strength (rpb = -0.523, p = 0.004), and Shoulder Mobility L had a negative correlation of moderate strength (rpb = -0.445, p = 0.016). This study determined that the Inline Lunge component of the FMS may be a key element in occupational task performance.

6.
J Clin Epidemiol ; 152: 201-208, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36404574

ABSTRACT

BACKGROUND AND OBJECTIVES: Traditionally, the minimal clinically important difference (MCID) is used to judge the meaningfulness of outcomes in total knee arthroplasty (TKA). However, MCID estimates do not consider patient costs, potential side effects, and inconveniences. MCIDs vary substantially across TKA studies and have several conceptual and psychometric problems. A more scientifically sound alternative for estimating benefits patients expect TKA is the smallest worthwhile effect (SWE), measured with the benefit-harm trade-off method. METHODS: We recruited 121 participants and followed them for 6 months after surgery. All participants completed Knee Injury and Osteoarthritis Score (KOOS) Pain and Function, and underwent an interview using the benefit-harm trade-off method. RESULTS: The absolute SWE at the 50th percentile (approximating the average patient) was 31 points KOOS Pain improvement and 28 points for KOOS Function, daily living. Construct validity was supported with strong associations between meeting SWE (yes or no) and satisfaction with 6-month outcome (yes or no) using Pearson Chi Square (24.5, P < 0.001). CONCLUSION: Current MCID-based methods for interpreting KOOS change scores have flaws while the SWE method is conceptually superior. We determined the SWE of TKA that would justify the costs, risks, and inconveniences of surgery. SWE estimates suggest that patients expect a substantially greater change in KOOS scores than would be expected using MCID estimates. Clinicians can use SWE estimates when discussing likely outcomes and potential TKA benefits and risks with their patients.


Subject(s)
Arthroplasty, Replacement, Knee , Osteoarthritis, Knee , Humans , Treatment Outcome , Minimal Clinically Important Difference , Knee Joint/surgery , Osteoarthritis, Knee/surgery , Pain
7.
Int J Sports Phys Ther ; 16(3): 854-861, 2021 Jun 01.
Article in English | MEDLINE | ID: mdl-34123537

ABSTRACT

BACKGROUND AND PURPOSE: Neck pain in the United States is pervasive and contributes to disability. While the majority of neck pain in young and healthy individuals is neuromusculoskeletal in nature, screening for red flags is necessary for ruling-out serious medical pathologies. The purpose of this case report is to describe a young and healthy male subject with a primary complaint of acute neck pain with multiple underlying upper extremity superficial vein thromboses (UESVTs). CASE DESCRIPTION: The subject was a 27-year-old male active-duty Soldier referred to physical therapy by his primary care provider (PCP) for acute left-sided neck pain. Prior to physical therapy, the subject had been treated with cyclobenzaprine, oxycodone-acetaminophen, trigger point injection and had undergone a D-dimer to rule out a potential thrombus due to air travel and lower extremity immobilization. OUTCOMES: The subject underwent a D-dimer, Doppler ultrasound, pharmacological treatment of Rivaroxaban, and was referred to hematology/oncology to rule out systemic causes of SVTs. Evidence of subtle increases in blood pressure over the course of three months, a positive D-dimer, and symptoms incongruent with clinical presentation contributed to referral to a hematology/oncology specialist and a diagnosis of multiple UESVTs. The subject was able to return to his previous level of activity by six months and remained free of SVTs at two-year follow-up. DISCUSSION: UESVT events are rare and can be challenging to identify. This case report describes a unique presentation of acute neck pain caused by underlying UESVTs in an otherwise healthy and active young male. LEVEL OF EVIDENCE: Level 4.

8.
Int J Sports Phys Ther ; 14(2): 228-236, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30997275

ABSTRACT

BACKGROUND: Several researchers have investigated functional testing with regard to return to sport decision making. Change of direction activities play a role in the advancement of rehabilitation as an athlete progresses towards return to sport. Few studies have assessed tests that measure change of direction tasks. PURPOSE: The primary purpose of this study was to establish test-retest and intra- and inter-rater reliability of performing the Change of Lateral Direction (COLD) test. The second purpose was to provide normative data for healthy college aged subjects performing the COLD test. The final purpose of this study was to assess the role of fatigue while performing lateral change of direction tasks. STUDY DESIGN: Cross-sectional, descriptive reliability study. METHODS: Thirty-three female and 18 male healthy college students (mean age = 25.5) were tested on two occasions, one week apart. Subjects started out standing on a standard 4" step and rapidly altered stepping to tape markers on either side of the step as many times as possible for 30 seconds. The total number of steps achieved in 30 seconds was video recorded and watched later to count steps in order to determine reliability. The effect of fatigue was assessed by subdividing the 30 second trial into three increments: 0-10 seconds (T0-10), 11-20 seconds (T11-20), and 21-30 seconds (T21-30). RESULTS: Normative data for session 1 and session 2 were 76.0 (±10.9) and 80.1 (±11.2) steps respectively. Inter-rater (ICC: 0.994-0.996) and intra-rater (ICC: 0.930-0.984) reliability was excellent. Test-retest reliability demonstrated a strong correlation (r = 0.88) between session 1 and session 2. A significant decline (p<0.001) in total number of steps was demonstrated between T0-10 and T21-30, as well as T11-20 and T21-30 during both session 1 and session 2. CONCLUSIONS: The COLD test demonstrated excellent inter-rater and intra-rater reliability. A possible fatigue effect occurred at T21-30. Because of the ease of administration, minimal equipment required, and excellent intra and inter-rater reliability, the COLD test provides an excellent functional change of direction test. This test could be used for serial reassessment during pre-season screening, rehabilitation, or return to sport. LEVEL OF EVIDENCE: 2c.

9.
Int J Sports Phys Ther ; 11(5): 746-756, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27757287

ABSTRACT

BACKGROUND: Clinical examination of caspuloligamentous structures of the glenohumeral joint has historically been subjective in nature, as demonstrated by limited intra-rater and inter-rater reproducibility. Musculoskeletal diagnostic ultrasound was utilized to develop a clinically objective measurement technique for glenohumeral inferior and posterolateral translation. PURPOSE: The purpose of this study was to measure the accessory passive force required to achieve end range glenohumeral posterolateral and inferior accessory translation, as well as, to quantify the amount of translation of the glenohumeral joint caused by the applied force. STUDY DESIGN: Cross-sectional descriptive correlational study. METHODS: Twenty-five asymptomatic subjects between the ages of 18 and 30 were recruited via convenience sampling. Posterolateral and inferior shoulder accessory passive translation was assessed and measured using a GE LOGIQe ultrasound, while concurrently using a hand held dynamometer to quantify the passive force applied during assessment. Normative values for force and translation were described as means and standard deviations. RESULTS: Mean values for posterolateral translation were 6.5 +/- 4.0 mm on the right shoulder and 6.3 +/- 3.5 mm on the left with an associated mean force of 127.1 +/- 55.6 N and 114.4 +/- 50.7 N, respectively. Mean values for inferior translation were 4.8 +/- 1.7 mm on the right shoulder and 5.4 +/- 1.8 mm on the left with an associated mean force of 84.5 +/- 30.5 N and 76.1 +/- 30.1 N, respectively. There was a significant association between inferior translation and inferior force (r = .51). No significant association was found between posterolateral translation and posterolateral force. Significant differences were found between dominant and non-dominant shoulders for posterolateral translation, posterolateral force to produce translation, and inferior translation values. CONCLUSIONS: Force data in the posterolateral and inferior direction is consistent with previously reported data for passive accessory motion testing at the shoulder. The results of this study provide data for glenohumeral translations and actual forces applied. Musculoskeletal diagnostic ultrasound can be a clinically relevant way to objectively measure the translation of the glenohumeral joint for assessing accessory passive motion joint translation while performing mobilizations or passive structure testing. This study provides a basis for comparison for healthy shoulder joints. LEVEL OF EVIDENCE: 2b.

10.
Health Info Libr J ; 33(3): 249-54, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27503692

ABSTRACT

This article provides a reflection on the outcomes of an international collaboration between health librarians and academics at York St John University and Pacific University Oregon. In particular, it describes how a month-long visiting professorship from an academic with a clinical librarian background at the Faculty of Health and Life Sciences helped to develop and inform teaching practice in the areas of information literacy and evidence-based health practice on health programmes at Pacific University. Perspectives are offered from both institutions on the rich exchange of knowledge and practice that took place during the visit and the ongoing impact it has had on teaching practices. H. S.


Subject(s)
Cooperative Behavior , Faculty/psychology , Internationality , Learning , Teaching , Curriculum , Evidence-Based Practice/methods , Health Literacy , Humans , Information Literacy , Library Services/statistics & numerical data , Oregon , United Kingdom
11.
Healthc Q ; 14(3): 66-74, 2011.
Article in English | MEDLINE | ID: mdl-21841379

ABSTRACT

This article shares the experiences of one acute care hospital as it made a concerted effort through a corporate initiative to improve patient throughput and quality of care despite competing demands and constrained resources. Organizational structures and specialized resources were employed to collect, analyze and use data in order to improve flow and access to care. The successes and lessons learned from this corporate initiative are summarized and may provide useful insights.


Subject(s)
Efficiency, Organizational , Emergency Service, Hospital/organization & administration , Patient Transfer/standards , Humans , Ontario , Organizational Case Studies , Quality Assurance, Health Care/organization & administration
12.
J Palliat Med ; 10(2): 304-7, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17472499

ABSTRACT

Although palliative care services are becoming increasingly prevalent in acute care hospitals only a minority of patients who die in hospital or in the community have seen palliative care teams. There are large numbers of patients who might benefit from palliative care who are not receiving it. That said, identification of patients who are eligible for these services, and of those who would most benefit is problematic. Limitations in our ability to accurately predict prognosis as well as lack of universal agreement as to what constitutes a terminal illness, or "end of life" are important considerations. Another significant challenge faced by our health care systems is whether or not all "end-of-life" patients require specialized care by trained palliative care providers. Even if this were the ideal model of care, this would be unfeasible given the relatively small number of trained providers compared to the aging and dying population. Therefore it is critical that health care systems begin to standardize their approach to the identification of patients who are most in need of, and/or most likely to benefit from interventions by interdisciplinary palliative care teams. Institutions that are planning to develop new services, or expand their current services will require some method/tool to assess specific population needs at their site. The Hamilton Chart Audit (H-CAT) was developed at our institution to help identify potential palliative care needs of patients and their families. We report on development of the tool and use of the tool for a retrospective audit of 222 patients who died at our institution.


Subject(s)
Medical Audit/methods , Oncology Service, Hospital/standards , Palliative Care/statistics & numerical data , Psychometrics/instrumentation , Referral and Consultation , Communication , Concurrent Review , Hospitals, University , Humans , Needs Assessment , Ontario , Pain Measurement , Patient Care Planning , Patient Care Team , Terminal Care/methods
13.
Biorheology ; 43(6): 729-46, 2006.
Article in English | MEDLINE | ID: mdl-17148856

ABSTRACT

The viscoelastic properties of blood are dominated by microstructures formed by red cells. The microstructures are of several types such as irregular aggregates, rouleaux, and layers of aligned cells. The dynamic deformability of the red cells, aggregation tendency, cell concentration, size of confining vessel and rate of flow are determining factors in the microstructure. Viscoelastic properties, viscosity and elasticity, relate to energy loss and storage in flowing blood while relaxation time and Weissenberg number play a role in assessing the importance of the elasticity relative to the viscosity. These effects are shown herein for flow in a large straight cylindrical tube, a small tube, and a porous medium. These cases approximate the geometries of the arterial system: large vessels, small vessels and vessels with many branches and bifurcations. In each case the viscosity, elasticity, relaxation time and Weissenberg number for normal human blood as well as blood with enhanced cell aggregation tendency and diminished cell deformability are given. In the smaller spaces of the microtubes and porous media, the diminished viscosity shows the possible influence of the Fåhraeus-Lindqvist effect and at high shear rates, the viscoelasticity of blood shows dilatancy. This is true for normal, aggregation enhanced and hardened cells.


Subject(s)
Blood Physiological Phenomena , Erythrocytes/physiology , Anemia, Sickle Cell/physiopathology , Blood Viscosity , Elasticity , Erythrocyte Aggregation , Erythrocyte Deformability , Humans
14.
Phys Ther ; 85(12): 1301-17, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16305269

ABSTRACT

BACKGROUND AND PURPOSE: Manual therapy and exercise have not previously been compared with a home exercise program for patients with osteoarthritis (OA) of the knee. The purpose of this study was to compare outcomes between a home-based physical therapy program and a clinically based physical therapy program. SUBJECTS: One hundred thirty-four subjects with OA of the knee were randomly assigned to a clinic treatment group (n=66; 61% female, 39% male; mean age [+/-SD]=64+/-10 years) or a home exercise group (n=68, 71% female, 29% male; mean age [+/-SD]=62+/-9 years). METHODS: Subjects in the clinic treatment group received supervised exercise, individualized manual therapy, and a home exercise program over a 4-week period. Subjects in the home exercise group received the same home exercise program initially, reinforced at a clinic visit 2 weeks later. Measured outcomes were the distance walked in 6 minutes and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). RESULTS: Both groups showed clinically and statistically significant improvements in 6-minute walk distances and WOMAC scores at 4 weeks; improvements were still evident in both groups at 8 weeks. By 4 weeks, WOMAC scores had improved by 52% in the clinic treatment group and by 26% in the home exercise group. Average 6-minute walk distances had improved about 10% in both groups. At 1 year, both groups were substantially and about equally improved over baseline measurements. Subjects in the clinic treatment group were less likely to be taking medications for their arthritis and were more satisfied with the overall outcome of their rehabilitative treatment compared with subjects in the home exercise group. DISCUSSION AND CONCLUSION: Although both groups improved by 1 month, subjects in the clinic treatment group achieved about twice as much improvement in WOMAC scores than subjects who performed similar unsupervised exercises at home. Equivalent maintenance of improvements at 1 year was presumably due to both groups continuing the identical home exercise program. The results indicate that a home exercise program for patients with OA of the knee provides important benefit. Adding a small number of additional clinical visits for the application of manual therapy and supervised exercise adds greater symptomatic relief.


Subject(s)
Exercise Therapy/methods , Home Care Services, Hospital-Based , Osteoarthritis, Knee/therapy , Physical Therapy Modalities , Female , Humans , Male , Middle Aged , Range of Motion, Articular , Walking
15.
Clin Hemorheol Microcirc ; 30(2): 83-97, 2004.
Article in English | MEDLINE | ID: mdl-15004333

ABSTRACT

Red blood cells containing hemoglobin S are less deformable than normal erythrocytes and have a major effect on the viscoelasticity of blood. This alteration in rheology increases the impedance to flow, leading to an increase in RBC aggregation and reduction in oxygen saturation, which induces further sickling and occlusions in the microcirculation. Patients with sickle cell disease (SCD) can experience severe complications, such as acute pain and stroke. Automated red blood cell exchange transfusion, or erythrocytapheresis, is used with homozygous SCD (Hb SS) to replace sickled cells with normal cells, thereby decreasing the percentage of sickle hemoglobin (%Hb S) and maintaining a net balance in iron accumulation. These patients received monthly erythrocytapheresis with a goal to maintain a pre-pheresis %Hb S at less than 30%. In this study, viscoelastic parameters were used to quantify the effectiveness of this therapy for six patients undergoing chronic erythrocytapheresis. Whole blood viscosity, elasticity and relaxation time at oscillatory strains of 0.2, 1 and 5, and hematocrit and %Hb S were measured prior to erythrocytapheresis and 15 minutes after completion and compared with normal reference values at the patient's hematocrit. This study confirms the beneficial effects on viscosity, elasticity, and relaxation time of erythrocytapheresis.


Subject(s)
Anemia, Sickle Cell/blood , Blood Component Removal , Blood Viscosity , Erythrocyte Transfusion/methods , Anemia, Sickle Cell/therapy , Blood Transfusion, Autologous , Elasticity , Erythrocyte Membrane , Hematocrit , Hemorheology , Humans , Membrane Fluidity , Reference Values , Treatment Outcome
16.
Clin Hemorheol Microcirc ; 30(1): 61-75, 2004.
Article in English | MEDLINE | ID: mdl-14967885

ABSTRACT

Red blood cells containing hemoglobin S are less deformable than normal erythrocytes and have a major effect on the viscoelasticity of blood. This alteration in rheology increases the impedance to flow, leading to an increase in RBC aggregation and reduction in oxygen saturation, which induces further sickling and occlusions in the microcirculation. Patients with sickle cell disease (SCD) can experience severe complications, such as acute pain and stroke. Automated red blood cell exchange transfusion, or erythrocytapheresis, is used in homozygous SCD (Hb SS) to replace sickled cells with normal cells, thereby decreasing the percentage of sickle hemoglobin (%Hb S) and maintaining a net balance in iron accumulation. These patients received monthly erythrocytapheresis with a goal to maintain a pre-pheresis %Hb S at less than 30%. In this study, viscoelastic parameters were used to quantify the effectiveness of this therapy for six patients undergoing chronic erythrocytapheresis. Whole blood viscosity, elasticity and relaxation time at oscillatory strains of 0.2, 1 and 5, and hematocrit and %Hb S were measured prior to erythrocytapheresis and 15 minutes after completion and compared with normal reference values at the patient's hematocrit. This study confirms the beneficial effects on viscosity, elasticity, and relaxation time of erythrocytapheresis.


Subject(s)
Anemia, Sickle Cell/blood , Anemia, Sickle Cell/therapy , Blood Viscosity , Cytapheresis , Erythrocyte Transfusion , Biomechanical Phenomena , Elasticity , Erythrocytes , Hematocrit , Hemoglobin, Sickle/analysis , Hemorheology , Humans , Treatment Outcome
18.
J Biol Chem ; 277(15): 12970-7, 2002 Apr 12.
Article in English | MEDLINE | ID: mdl-11773073

ABSTRACT

The BAH genomic locus encodes three distinct proteins: junctin, humbug, and BAH. All three proteins share common exons, but differ significantly based upon the use of alternative terminal exons. The biological roles of BAH and humbug and their functional relationship to junctin remain unclear. To evaluate the role of BAH in vivo, the catalytic domain of BAH was specifically targeted such that the coding regions of junctin and humbug remained undisturbed. BAH null mice lack measurable BAH protein in several tissues, lack aspartyl beta-hydroxylase activity in liver preparations, and exhibit no hydroxylation of the epidermal growth factor (EGF) domain of clotting Factor X. In addition to reduced fertility in females, BAH null mice display several developmental defects including syndactyly, facial dysmorphology, and a mild defect in hard palate formation. The developmental defects present in BAH null mice are similar to defects observed in knock-outs and hypomorphs of the Notch ligand Serrate-2. In this work, beta-hydroxylation of Asp residues in EGF domains is demonstrated for a soluble form of a Notch ligand, human Jagged-1. These results along with recent reports that another post-translational modification of EGF domains in Notch gene family members (glycosylation by Fringe) alters Notch pathway signaling, lends credence to the suggestion that aspartyl beta-hydroxylation may represent another post-translational modification of EGF domains that can modulate Notch pathway signaling. Previous work has demonstrated increased levels of BAH in certain tumor tissues and a role for BAH in tumorigenesis has been proposed. The role of hydroxylase in tumor formation was tested directly by crossing BAH KO mice with an intestinal tumor model, APCmin mice. Surprisingly, BAH null/APCmin mice show a statistically significant increase in both intestinal polyp size and number when compared with BAH wild-type/APCmin controls. These results suggest that, in contrast to expectations, loss of BAH catalytic activity may promote tumor formation.


Subject(s)
Epidermal Growth Factor/metabolism , Intestinal Neoplasms/genetics , Mixed Function Oxygenases/genetics , Protein Processing, Post-Translational , Amino Acid Sequence , Animals , Catalytic Domain , Exons , Female , Hydroxylation , Incidence , Male , Membrane Proteins/metabolism , Mice , Mice, Knockout , Receptors, Notch
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