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1.
Leukemia ; 31(7): 1513-1524, 2017 07.
Article in English | MEDLINE | ID: mdl-28210003

ABSTRACT

Two major types of leukemogenic BCR-ABL fusion proteins are p190BCR-ABLand p210BCR-ABL. Although the two fusion proteins are closely related, they can lead to different clinical outcomes. A thorough understanding of the signaling programs employed by these two fusion proteins is necessary to explain these clinical differences. We took an integrated approach by coupling protein-protein interaction analysis using biotinylation identification with global phosphorylation analysis to investigate the differences in signaling between these two fusion proteins. Our findings suggest that p190BCR-ABL and p210BCR-ABL differentially activate important signaling pathways, such as JAK-STAT, and engage with molecules that indicate interaction with different subcellular compartments. In the case of p210BCR-ABL, we observed an increased engagement of molecules active proximal to the membrane and in the case of p190BCR-ABL, an engagement of molecules of the cytoskeleton. These differences in signaling could underlie the distinct leukemogenic process induced by these two protein variants.


Subject(s)
Fusion Proteins, bcr-abl/physiology , Signal Transduction/physiology , Cytoskeletal Proteins/metabolism , Humans , Leukemia/etiology , Phosphorylation , STAT Transcription Factors/physiology
4.
Am J Transplant ; 12(6): 1392-7, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22487555

ABSTRACT

We propose a Medicare Demonstration Project to develop a standard acquisition charge for kidney paired donation. A new payment strategy is required because Medicare and commercial insurance companies may not directly pay living donor costs intended to lead to transplantation of a beneficiary of a different insurance provider. Until the 1970s, when organ procurement organizations were empowered to serve as financial intermediaries to pay the upfront recovery expenses for deceased donor kidneys before knowing the identity of the recipient, there existed similar limitations in the recovery and placement of deceased donor organs. Analogous to the recovery of deceased donor kidneys, kidney paired donation requires the evaluation of living donors before identifying their recipient. Tissue typing, crossmatching and transportation of living donors or their kidneys represent additional financial barriers. Finally, the administrative expenses of the organizations that identify and coordinate kidney paired donation transplantation require reimbursement akin to that necessary for organ procurement organizations. To expand access to kidney paired donation for more patients, we propose a model to reimburse paired donation expenses analogous to the proven strategy used for over 30 years to pay for deceased donor solid organ transplantation in America.


Subject(s)
Kidney Transplantation , Tissue Donors , Tissue and Organ Procurement/economics , Humans
5.
Leukemia ; 26(7): 1730-41, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22307178

ABSTRACT

Flow cytometry (FC) is increasingly recognized as an important tool in the diagnosis and prognosis of myelodysplastic syndromes (MDS). However, validation of current assays and agreement upon the techniques are prerequisites for its widespread acceptance and application in clinical practice. Therefore, a working group was initiated (Amsterdam, 2008) to discuss and propose standards for FC in MDS. In 2009 and 2010, representatives from 23, mainly European, institutes participated in the second and third European LeukemiaNet (ELN) MDS workshops. In the present report, minimal requirements to analyze dysplasia are refined. The proposed core markers should enable a categorization of FC results in cytopenic patients as 'normal', 'suggestive of', or 'diagnostic of' MDS. An FC report should include a description of validated FC abnormalities such as aberrant marker expression on myeloid progenitors and, furthermore, dysgranulopoiesis and/or dysmonocytopoiesis, if at least two abnormalities are evidenced. The working group is dedicated to initiate further studies to establish robust diagnostic and prognostic FC panels in MDS. An ultimate goal is to refine and improve diagnosis and prognostic scoring systems. Finally, the working group stresses that FC should be part of an integrated diagnosis rather than a separate technique.


Subject(s)
Biomarkers, Tumor/metabolism , Flow Cytometry/standards , Myelodysplastic Syndromes/diagnosis , Myelodysplastic Syndromes/metabolism , Practice Guidelines as Topic/standards , Bone Marrow/metabolism , Bone Marrow/pathology , Flow Cytometry/methods , Humans , Immunophenotyping , International Agencies , Myelodysplastic Syndromes/immunology , Prognosis , Reference Standards , Societies, Scientific
6.
Haemophilia ; 16(6): 937-42, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20546033

ABSTRACT

Coagulation factor V (FV) has an important role in the blood coagulation cascade, in both the pro- and anticoagulant pathways. FV deficiency is a rare bleeding disorder with variable phenotypic expression. We report a cohort of 10 patients with mild-severe FV deficiency in whom a total of 11 novel mutations were identified. Three patients were compound heterozygous for two mutations, whereas each of the remaining patients had a single heterozygous variant. FV levels did not correlate with either the type of mutation identified or the bleeding diathesis exhibited by the patients. Although considered to have an autosomal recessive mode of inheritance, patients with a single missense mutation may present with a significant bleeding history. The addition of a significant number of previously unidentified mutations to the public domain will contribute to the knowledge and understanding of the molecular pathology of this rare disorder.


Subject(s)
Factor V Deficiency/genetics , Factor V/genetics , Mutation , Adolescent , Adult , Cohort Studies , DNA Mutational Analysis , Genotype , Heterozygote , Homozygote , Humans , Middle Aged , Mutation, Missense/genetics , Phenotype , Reverse Transcriptase Polymerase Chain Reaction , Sequence Analysis, DNA , Young Adult
7.
Am J Transplant ; 10(3): 458-63, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20055800

ABSTRACT

There are significant risks and inefficiencies associated with organ procurement travel. In an effort to identify, quantify, and define opportunities to mitigate these risks and inefficiencies, 25 experts from the transplantation, transportation and insurance fields were convened. The forum concluded that: on procurement travel practices are inadequate, there is wide variation in the quality of aero-medical transportation, current travel practices for organ procurement are inefficient and there is a lack of standards for organ procurement travel liability coverage. The forum concluded that the transplant community should require that air-craft vendors adhere to industry quality standards compatible with the degree of risk in their mission profiles. Within this context, a purchasing collaborative within the transplant community may offer opportunities for improved service and safety with lower costs. In addition, changes in travel practices should be considered with broader sharing of procurement duties across centers. Finally, best practice standards should be instituted for life insurance for transplant personnel and liability insurance for providers. Overall, the aims of these proposals are to raise procurement travel standards and in doing so, to improve the transplantation as a whole.


Subject(s)
Organ Transplantation/economics , Organ Transplantation/methods , Tissue Donors , Tissue and Organ Procurement/standards , Transportation , Aircraft , Humans , Liability, Legal , Michigan , Organ Transplantation/legislation & jurisprudence , United States
9.
Clin Appl Thromb Hemost ; 12(2): 237-9, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16708129

ABSTRACT

A patient with type 2A von Willebrand disease and a long history of gastrointestinal (GI) bleeding is presented, in whom no abnormality was found on sequencing the von Willebrand factor gene at the DNA level. Subsequent RNA analysis revealed him to be heterozygous for a T-C substitution at nucleotide 4,883, a mutation previously described and associated with type 2A von Willebrand disease. This illustrates the value of a dual DNA/ RNA approach to genetic investigations of highly polymorphic genes. GI bleeding from angiodysplasia is a feature of von Willebrand disease, particularly type 2A. Proactive management with definitive diagnosis of angiodysplasia and ablative treatment where feasible is recommended to stop bleeding symptoms and minimize exposure to blood products.


Subject(s)
von Willebrand Diseases/diagnosis , von Willebrand Diseases/therapy , von Willebrand Factor/genetics , Angiodysplasia/diagnosis , DNA/genetics , DNA Mutational Analysis/methods , Gastrointestinal Hemorrhage , Humans , Male , Middle Aged , Point Mutation , RNA/genetics , von Willebrand Diseases/complications
10.
J Hum Hypertens ; 19(1): 33-45, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15372064

ABSTRACT

Sodium reduction is efficacious for primary prevention of hypertension, but the feasibility of achieving this effect is unclear. The objective of the paper is detailed analyses of adherence to and effects of the sodium reduction intervention among overweight adults in the Trials of Hypertension Prevention, Phase II. Sodium reduction (comprehensive education and counselling about how to reduce sodium intake) was tested vs no dietary intervention (usual care) for 36-48 months. A total of 956 white and 203 black adults, ages 30-54 years, with diastolic blood pressure 83-89 mmHg, systolic blood pressure (SBP) <140 mmHg, and body weight 110-165% of gender-specific standard weight were included in the study. At 36 months, urinary sodium excretion was 40.4 mmol/24 h (24.4%) lower in sodium reduction compared to usual care participants (P<0.0001), but only 21% of sodium reduction participants achieved the targeted level of sodium excretion below 80 mmol/24 h. Adherence was positively related to attendance at face-to-face contacts. Net decreases in SBP at 6, 18, and 36 months of 2.9 (P<0.001), 2.0 (P<0.001), and 1.3 (P=0.02) mmHg in sodium reduction vs usual care were associated with an overall 18% lower incidence of hypertension (P=0.048); were relatively unchanged by adjustment for ethnicity, gender, age, and baseline blood pressure, BMI, and sodium excretion; and were observed in both black and white men and women. From these beneficial but modest results with highly motivated and extensively counselled individuals, sodium reduction sufficient to favourably influence the population blood pressure distribution will be difficult to achieve without food supply changes.


Subject(s)
Diet, Sodium-Restricted , Directive Counseling , Hypertension/prevention & control , Obesity/diet therapy , Adult , Angiotensins/genetics , Black People , Female , Follow-Up Studies , Genotype , Humans , Hypertension/etiology , Male , Middle Aged , Obesity/complications , Patient Compliance/ethnology , Sex Factors , Treatment Outcome , White People
11.
J Hum Hypertens ; 19(1): 47-54, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15343354

ABSTRACT

A cross-sectional dose-response relationship between sodium intake and blood pressure (BP) has been demonstrated, but evidence for a graded longitudinal effect is limited. Evaluation of BP response to sodium reduction was assessed in a 3-year lifestyle dietary intervention trial. BP changes at 18 and 36 months after enrollment were analysed according to concurrent quantitative changes in sodium excretion and by categories of success in sodium reduction among 1157 men and women, ages 30-54 years, with a diastolic BP (DBP) 83-89 mmHg, systolic BP (SBP) <140 mmHg, body weight 110-165% of sex-specific standard weight, and valid baseline urinary sodium excretion. Participants were randomized to a Sodium Reduction intervention (n=581) or Usual Care (n=576). From a 187 mmol/24 h baseline mean sodium excretion, net decreases were 44 mmol/24 h at 18 months and 38 mmol/24 h at 36 months in Sodium Reduction vs Usual Care. Corresponding net decreases in SBP/DBP were 2.0/1.4 mmHg at 18 months, and 1.7/0.9 mmHg at 36 months. Significant dose-response trends in BP change over quintiles of achieved sodium excretion were seen at both 18 (SBP and DBP) and 36 (SBP only) months; effects appeared stronger among those maintaining sodium reduction. Estimated SBP decreases per 100 mmol/24 h reduction in sodium excretion at 18 and 36 months were 2.2 and 1.3 mmHg before and 7.0 and 3.6 mmHg after correction for measurement error, respectively. DBP changes were smaller and nonsignificant at 36 months. In conclusion, incremental decreases in BP with lower sodium excretion were observed in these overweight nonhypertensive individuals.


Subject(s)
Blood Pressure/drug effects , Diet, Sodium-Restricted , Obesity/physiopathology , Sodium, Dietary/administration & dosage , Adult , Directive Counseling , Dose-Response Relationship, Drug , Female , Follow-Up Studies , Humans , Male , Middle Aged , Obesity/diet therapy , Sodium, Dietary/urine
12.
Hum Mutat ; 19(3): 274-8, 2002 Mar.
Article in English | MEDLINE | ID: mdl-11857744

ABSTRACT

Hemophilia A is a bleeding disorder caused by a quantitative or qualitative deficiency in the coagulation factor VIII. Causative mutations are heterogeneous in nature and are distributed throughout the FVIII gene. With the exception of mutations that result in prematurely truncated protein, it has proved difficult to correlate mutation type/amino acid substitution with severity of disease. We have identified 81 mutations in 96 unrelated patients, all of whom have typed negative for the common IVS-22 inversion mutation. Forty-one of these mutations are not recorded on F8C gene mutation databases. We have analyzed these 41 mutations with regard to location, whether or not each is a cross-species conserved region, and type of substitution and correlated this information with the clinical severity of the disease. Our findings support the view that the phenotypic result of a mutation in the FVIII gene correlates more with the position of the amino acid change within the 3D structure of the protein than with the actual nature of the alteration.


Subject(s)
Factor VIII/genetics , Mutation/genetics , Animals , Codon, Nonsense/genetics , DNA Mutational Analysis/methods , Dogs , Female , Genotype , Hemophilia A/blood , Hemophilia A/genetics , Humans , Mice , Mutagenesis, Insertional/genetics , Mutation, Missense/genetics , Phenotype , Polymorphism, Single-Stranded Conformational , RNA Splice Sites/genetics , Sequence Deletion/genetics
14.
Blood Coagul Fibrinolysis ; 12(1): 33-6, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11229824

ABSTRACT

A simple, rapid and cost-effective method for the analysis of three of the most widely screened genetic risk factors for thrombosis has been established. The protocol developed uses blood spots stored on filter paper (Guthrie spots) as well as DNA extracted from anticoagulated blood. The use of Guthrie spots taken at birth enables the retrospective study of patients who develop thrombotic complications without necessitating resampling. Following isolation of DNA, conventional fluorescence-labelled polymerase chain reaction (PCR) is performed using a thermostable DNA polymerase. Denatured, single-stranded PCR products are analysed on a semi-automated capillary-based genetic analyser, the data being stored electronically. This sensitive protocol obviates the need for endonuclease digestion and the associated gel running and documentation, and leads to a reduction in the recurrent costs of laboratory consumables.


Subject(s)
Genetic Testing/methods , Thrombosis/genetics , Blood Specimen Collection/methods , Cost-Benefit Analysis , DNA Mutational Analysis/methods , DNA Mutational Analysis/standards , Electronic Data Processing , Fluorescent Dyes , Genetic Markers , Genetic Testing/economics , Genetic Testing/standards , Humans , Polymorphism, Single-Stranded Conformational , Retrospective Studies , Risk Factors , Thrombosis/diagnosis
15.
Clin Appl Thromb Hemost ; 6(3): 181-3, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10898281

ABSTRACT

We report a case of spontaneous left pulmonary artery thrombosis in a 3-day-old male neonate. The presentation of heparin resistance and thrombosis raised the possibility of a type II heparin binding site antithrombin deficiency. A continuous infusion of antithrombin concentrate was used successfully, following failure of plasma, to correct the heparin resistance. Rapid genetic analysis allowed sequencing of the antithrombin gene within 5 working days. This showed the infant to be homozygous for the substitution of C to T at nucleotide 2759. This base change causes mutation of the native leucine at codon 99 to a phenylalanine. This antithrombin variant has been previously reported (antithrombin Budapest 3) and results in reduced binding of heparin to antithrombin. Such a molecular diagnostic approach is feasible and warranted in such cases of neonatal thrombosis because of the diagnostic difficulties encountered.


Subject(s)
Antithrombin III Deficiency/genetics , Pulmonary Embolism/diagnosis , Pulmonary Embolism/genetics , Base Sequence , Blood Component Transfusion , Cytosine , Female , Heparin/therapeutic use , Homozygote , Humans , Infant, Newborn , Male , Parents , Partial Thromboplastin Time , Point Mutation , Pulmonary Embolism/therapy , Thymine
16.
Indian Heart J ; 52(7 Suppl): S44-52, 2000.
Article in English | MEDLINE | ID: mdl-11339440

ABSTRACT

A nested case-control study was undertaken involving men participating in the Multiple Risk Factor Intervention Trial (MRFIT). Serum samples from 712 men, stored for upto 20 years, were analysed for homocyst(e)ine. Cases involved non-fatal myocardial infractions, identified through the active phase of the study, which ended on February 28, 1982, and deaths due to coronary heart disease, monitored through 1990. The non-fatal myocardial infarction occurred within 7 years of sample collection, whereas the majority of coronary heart disease deaths occurred more than 11 years after sample collection. Mean homocyst(e)ine concentrations were in the expected range and did not differ significantly between case patients and control subjects: myocardial infarction cases, 12.6 micromol/L; myocardial infarction controls, 13.1 micromol/L; coronary heart disease death cases, 12.8 micromol/L; and coronary heart disease controls, 12.7 micromol/L. Odds ratios versus quartile 1 for coronary heart disease deaths and myocardial infarctions combined were as follows: quartile 2, 1.03; quartile 3, 0.84; and quartile 4, 0.92. Thus, in this prospective study, no association of homocyst(e)ine concentration with heart disease was detected. Homocyst(e)ine levels were weakly associated with the acute-phase (C-reactive) protein. These results are discussed with respect to the suggestion that homocyst(e)ine is an independent risk factor for heart disease.


Subject(s)
Coronary Disease/etiology , Homocysteine/adverse effects , Homocysteine/blood , Myocardial Infarction/etiology , Case-Control Studies , Coronary Disease/mortality , Humans , Male , Middle Aged , Myocardial Infarction/mortality , Odds Ratio , Risk Factors
17.
J Am Diet Assoc ; 99(8 Suppl): S12-8, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10450289

ABSTRACT

Epidemiologic studies across societies have shown consistent differences in blood pressure that appear to be related to diet. Vegetarian diets are consistently associated with reduced blood pressure in observational and interventional studies, but clinical trials of individual nutrient supplements have had an inconsistent pattern of results. Dietary Approaches to Stop Hypertension (DASH) was a multicenter, randomized feeding study, designed to compare the impact on blood pressure of 3 dietary patterns. DASH was designed as a test of eating patterns rather than of individual nutrients in an effort to identify practical, palatable dietary approaches that might have a meaningful impact on reducing morbidity and mortality related to blood pressure in the general population. The objectives of this article are to present the scientific rationale for this trial, review the methods used, and discuss important design considerations and implications.


Subject(s)
Diet , Hypertension/diet therapy , Randomized Controlled Trials as Topic , Research Design , Adult , Blood Pressure , Diet, Vegetarian , Humans , Hypertension/epidemiology , Multicenter Studies as Topic
18.
Clin Cardiol ; 22(7 Suppl): III6-10, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10410299

ABSTRACT

BACKGROUND: Populations eating mainly vegetarian diets have lower blood pressure levels than those eating omnivorous diets. Epidemiologic findings suggest that eating fruits and vegetables lowers blood pressure. HYPOTHESIS: Two hypotheses were tested: (1) that high intake of fruits and vegetables lowers blood pressure, and (2) that an overall dietary pattern (known as the DASH diet, or DASH combination diet) that is high in fruits, vegetables, nuts, and low-fat dairy products, emphasizes fish and chicken rather than red meat, and is low in saturated fat, cholesterol, sugar, and refined carbohydrate lowers blood pressure. METHODS: Participants were 459 adults with untreated systolic blood pressure < 160 mmHg and diastolic blood pressure 80-95 mmHg. After a 3-week run-in on a control diet typical of Americans, they were randomized to 8 weeks receiving either the control diet, or a diet rich in fruits and vegetables, or the DASH diet. The participants were given all of their foods to eat, and body weight and sodium intake were held constant. Blood pressure was measured at the clinic and by 24-h ambulatory monitoring. RESULTS: The DASH diet lowered systolic blood pressure significantly in the total group by 5.5/3.0 mmHg, in African Americans by 6.9/3.7 mmHg, in Caucasians by 3.3/2.4 mmHg, in hypertensives by 11.6/5.3 mmHg, and in nonhypertensives by 3.5/2.2 mmHg. The fruits and vegetables diet also reduced blood pressure in the same subgroups, but to a lesser extent. The DASH diet lowered blood pressure similarly throughout the day and night. CONCLUSIONS: The DASH diet may offer an alternative to drug therapy in hypertensives and, as a population approach, may prevent hypertension, particularly in African Americans.


Subject(s)
Diet , Hypertension/diet therapy , Life Style , Adult , Female , Fruit , Humans , Hypertension/prevention & control , Male , Middle Aged , Nuts , Randomized Controlled Trials as Topic , Treatment Outcome , Vegetables
19.
Clin Exp Hypertens ; 21(5-6): 769-83, 1999.
Article in English | MEDLINE | ID: mdl-10423100

ABSTRACT

From a world-wide, population perspective, the problem of excessive blood pressure levels for optimal cardiovascular health is immense and growing. Evidence from animal experimentation, observational epidemiology, and randomized clinical trials strongly supports efforts to change nutritional factors in desirable directions, especially to lower dietary salt and increase potassium intake.


Subject(s)
Potassium, Dietary/metabolism , Sodium Chloride, Dietary/adverse effects , Adult , Age Factors , Blood Pressure , Body Weight , Clinical Trials as Topic , Diet, Sodium-Restricted , Female , Humans , Hypertension/etiology , Hypertension/therapy , Male , Middle Aged , Sodium Chloride, Dietary/metabolism
20.
Arch Fam Med ; 8(3): 228-36, 1999.
Article in English | MEDLINE | ID: mdl-10333818

ABSTRACT

BACKGROUND: National guidelines recommend consideration of step down or withdrawal of medication in patients with well-controlled hypertension, but knowledge of factors that predict or mediate success in achieving this goal is limited. OBJECTIVE: To identify patient characteristics associated with success in controlling blood pressure (BP) after withdrawal of antihypertensive medication. DESIGN: The Trial of Nonpharmacologic Interventions in the Elderly tested whether lifestyle interventions designed to promote weight loss or a reduced intake of sodium, alone or in combination, provided satisfactory BP control among elderly patients (aged 60-80 years) with hypertension after withdrawal from antihypertensive drug therapy. Participants were observed for 15 to 36 months after attempted drug withdrawal. MAIN OUTCOME MEASURES: Trial end points were defined by (1) a sustained BP of 150/90 mm Hg or higher, (2) a clinical cardiovascular event, or (3) a decision by participants or their personal physicians to resume BP medication. RESULTS: Proportional hazards regression analyses indicated that the hazard (+/- SE) of experiencing an end point among persons assigned to active interventions was 75% +/- 9% (weight loss), 68% +/- 7% (sodium reduction), and 55% +/- 7% (combined weight loss/sodium reduction) that of the hazard for those assigned to usual care. Lower baseline systolic BP (P < .001), fewer years since diagnosis of hypertension (P < .001), fewer years of antihypertensive treatment (P < .001), and no history of cardiovascular disease (P = .01) were important predictors of maintaining successful nonpharmacological BP control throughout follow-up, based on logistic regression analysis. Age, ethnicity, baseline level of physical activity baseline weight, medication class, smoking status, and alcohol intake were not statistically significant predictors. During follow-up, the extent of weight loss (P = .001) and urinary sodium excretion (P = .04) were associated with a reduction in the risk of trial end points in a graded fashion. CONCLUSIONS: Withdrawal from antihypertensive medication is most likely to be successful in patients with well-controlled hypertension who have been recently (within 5 years) diagnosed or treated, and who adhere to life-style interventions involving weight loss and sodium reduction. More than 80% of these patients may have success in medication withdrawal for longer than 1 year.


Subject(s)
Antihypertensive Agents/administration & dosage , Life Style , Aged , Aged, 80 and over , Alcohol Drinking , Drug Administration Schedule , Exercise , Female , Humans , Logistic Models , Male , Middle Aged , Proportional Hazards Models , Smoking , Sodium, Dietary/administration & dosage , Time Factors , Weight Loss
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